技术领域technical field
本发明涉及无线通信领域，特别涉及一种声波通信中信号处理与传输的发送方法和装置。The invention relates to the field of wireless communication, in particular to a sending method and device for signal processing and transmission in acoustic wave communication.
背景技术Background technique
对于目前常用的局域、近场通信技术，如蓝牙和WiFi，在通信前需要通信双方进行配对，并且需要外加设备；而NFC/RIFD技术通常也需要专门的设备，并且往往用于数据的单向传输。对于用于数据传输的声波通信领域技术，常用的是超声波通信，这也需要额外的装置才可实现，这都将造成传输成本提高，同时也难以保证技术实施效率。For the currently commonly used local area and near-field communication technologies, such as Bluetooth and WiFi, both communication parties need to be paired before communication, and additional equipment is required; while NFC/RIFD technology usually also requires special equipment, and is often used for data exchange. to transfer. For the technology in the field of acoustic wave communication for data transmission, ultrasonic communication is commonly used, which also requires additional devices to realize, which will increase the cost of transmission, and it is also difficult to ensure the efficiency of technology implementation.
目前，一般便携式设备能够播放和录音的频率范围为0～22KHz。在0～2KHz频段干扰较为严重(包括人说话的声音，周围环境的声音等)，不适于数据传输。现有技术中存在采用16KHz～22KHz的频率范围作为通信频率的做法，事实上对于16KHz～18KHz频段，播放和录音的时候信号衰减严重，由于手机的麦克风和扬声器的质量参差不齐，因此这样的声音频段并不能很好的适配各类型的手机，也不适用于数据传输。At present, the frequency range that a general portable device can play and record is 0-22KHz. The interference in the 0-2KHz frequency band is relatively serious (including the voice of people speaking, the sound of the surrounding environment, etc.), which is not suitable for data transmission. In the prior art, there is a practice of using the frequency range of 16KHz to 22KHz as the communication frequency. In fact, for the frequency range of 16KHz to 18KHz, the signal attenuation is serious during playback and recording. Due to the uneven quality of the microphone and speaker of the mobile phone, such The sound frequency range is not well adapted to various types of mobile phones, nor is it suitable for data transmission.
一公开专利技术提及采用频率映射即类似于FSK的方式将数据进行20Hz～20kHz的声波频率调制，然而为保证数据的可靠传输，需要将每个传输的频率保持在50ms；另一公开专利技术中则需保证频率传输持续40ms，并且还需要发送端与接收端同步。可想而知，当数据量较大的时候，这样的传输方式需要的传输时间是非常大的，所以其效率较低。One published patent technology mentions the use of frequency mapping, which is similar to FSK, to modulate the data with an acoustic wave frequency of 20 Hz to 20 kHz. However, in order to ensure reliable data transmission, the frequency of each transmission needs to be kept at 50 ms; another disclosed patent technology In the middle, it is necessary to ensure that the frequency transmission lasts for 40ms, and the sending end and the receiving end need to be synchronized. It is conceivable that when the amount of data is large, the transmission time required by such a transmission method is very large, so its efficiency is low.
OFDM(OrthogonalFrequencyDivisionMultiplexing)即正交频分复用技术，实际上OFDM是MCM(MultiCarrierModulation)，多载波调制的一种。OFDM的主要思想是：将信道分成若干正交子信道，将高速数据信号转换成并行的低速子数据流，调制到在每个子信道上进行传输。正交信号可以通过在接收端采用相关技术来分开，这样可以减少子信道之间的相互干扰(ICI)。每个子信道上的信号带宽小于信道的相关带宽，因此每个子信道上可以看成平坦性衰落，从而可以消除码间串扰，而且由于每个子信道的带宽仅仅是原信道带宽的一小部分，信道均衡变得相对容易。OFDM (Orthogonal Frequency Division Multiplexing) is Orthogonal Frequency Division Multiplexing technology. In fact, OFDM is MCM (MultiCarrier Modulation), a type of multi-carrier modulation. The main idea of OFDM is to divide the channel into several orthogonal sub-channels, convert high-speed data signals into parallel low-speed sub-data streams, and modulate them for transmission on each sub-channel. Orthogonal signals can be separated by using correlation techniques at the receiver, which can reduce the mutual interference (ICI) between sub-channels. The signal bandwidth on each sub-channel is smaller than the relevant bandwidth of the channel, so each sub-channel can be regarded as flat fading, which can eliminate intersymbol interference, and because the bandwidth of each sub-channel is only a small part of the original channel bandwidth, the channel Equilibrium becomes relatively easy.
OFDM调制技术具有抗干扰、抗频率衰减等特性，一般应用于高频、宽带传输领域，而较少应用于声波通信领域。OFDM modulation technology has the characteristics of anti-interference and anti-frequency attenuation. It is generally used in the field of high-frequency and broadband transmission, but less used in the field of acoustic wave communication.
发明内容Contents of the invention
基于此，需要提供一种具有良好终端适应性、高传输效率、低成本投入的声波通信技术方案。Based on this, it is necessary to provide an acoustic wave communication technology solution with good terminal adaptability, high transmission efficiency, and low-cost investment.
为实现上述目的，发明人提供了一种声波通信发送方法，包括步骤：In order to achieve the above purpose, the inventor provides a method for sending acoustic wave communication, including steps:
对一数据单元进行如下处理：A data unit is processed as follows:
设置校验编码；Set the check code;
将所述数据单元按预设编码规则调制到M个载波上，M为大于或等于2的正整数，所述M个载波满足两两正交的关系，且M个载波中任意两个载波的频率差值的绝对值小于或等于22kHz；所述编码规则包括相位参数或幅度参数；The data unit is modulated onto M carriers according to a preset coding rule, M is a positive integer greater than or equal to 2, and the M carriers satisfy a pairwise orthogonal relationship, and any two carriers among the M carriers The absolute value of the frequency difference is less than or equal to 22kHz; the encoding rule includes a phase parameter or an amplitude parameter;
加入同步码；Add synchronization code;
加入循环前缀；add a cyclic prefix;
生成声音信号。Generate an acoustic signal.
进一步地，所述的声波通信发送方法中，步骤“将所述数据单元按预设编码规则调制到M个载波上”具体包括：Further, in the acoustic wave communication sending method, the step of "modulating the data unit onto M carriers according to preset encoding rules" specifically includes:
将数据单元按预设转换规则转换为一组复数序列，并按预设选取规则从该复数序列中选取M个复数，并将该M个复数与(N-M)个0以预设组成规则组成一长度为N的数据组，并对该数据组做N点傅里叶逆变换；其中N>M且N＝2i，i为正整数；Convert the data unit into a set of complex number sequences according to the preset conversion rules, and select M complex numbers from the complex number sequence according to the preset selection rules, and combine the M complex numbers and (NM) 0s into a set according to the preset composition rules A data group with a length of N, and performing an N-point Fourier inverse transform on the data group; where N>M and N=2i , i is a positive integer;
连接所有傅里叶逆变换结果信号得到调制结果信号。Concatenate all inverse Fourier transform result signals to obtain the modulated result signal.
进一步地，所述的声波通信发送方法中，所述数据单元包括数据长度、分组数目或分组编号，并且数据长度、分组数目或分组编号的数值均小于或等于255。Further, in the acoustic wave communication sending method, the data unit includes a data length, a group number or a group number, and the values of the data length, group number or group number are all less than or equal to 255.
进一步地，所述的声波通信发送方法中，M的取值为2-64，且M个载波中任意两个载波的频率差值的绝对值范围为86Hz-16kHz。Further, in the acoustic wave communication sending method, the value of M is 2-64, and the absolute value range of the frequency difference between any two carriers among the M carriers is 86 Hz-16 kHz.
进一步地，所述的声波通信发送方法中，M的取值为2-16，且M个载波中任意两个载波的频率差值的绝对值范围为750Hz-3kHz。Further, in the acoustic wave communication sending method, the value of M is 2-16, and the absolute value range of the frequency difference between any two carriers among the M carriers is 750 Hz-3 kHz.
进一步地，所述的声波通信发送方法中，步骤“生成声音信号”所生成的声音信号的频率位于下述范围：Further, in the acoustic wave communication sending method, the frequency of the acoustic signal generated in the step "generating the acoustic signal" is in the following range:
(93.75*0.9*k-93.75*1.1*k)Hz，(93.75*0.9*k-93.75*1.1*k)Hz,
(86.13*0.9*k-86.13*1.1*k)Hz，(86.13*0.9*k-86.13*1.1*k)Hz,
(78.13*0.9*k-78.13*1.1*k)Hz，(78.13*0.9*k-78.13*1.1*k)Hz,
(62.5*0.9*k-62.5*1.1*k)Hz，或(62.5*0.9*k-62.5*1.1*k)Hz, or
(43.1*0.9*k-43.1*1.1*k)Hz，其中k＝0,1,...,255。(43.1*0.9*k-43.1*1.1*k)Hz, where k=0,1,...,255.
发明人还提供了一种声波通信发送装置，包括校验设置模块、调制模块、同步码模块、循环前缀模块和声音生成模块；The inventor also provides a sound wave communication sending device, including a verification setting module, a modulation module, a synchronization code module, a cyclic prefix module and a sound generation module;
所述校验模块用于对数据单元设置校验编码；The verification module is used to set a verification code for the data unit;
所述调制模块用于将所述数据单元按预设编码规则调制到M个载波上，M为大于或等于2的正整数，所述M个载波满足两两正交的关系，且M个载波中任意两个载波的频率差值的绝对值小于或等于22kHz；所述编码规则包括相位参数或幅度参数；The modulation module is used to modulate the data unit onto M carriers according to a preset coding rule, M is a positive integer greater than or equal to 2, and the M carriers satisfy a pairwise orthogonal relationship, and the M carriers The absolute value of the frequency difference between any two carriers in is less than or equal to 22kHz; the encoding rule includes a phase parameter or an amplitude parameter;
所述同步码模块用于加入同步码；The synchronization code module is used to add a synchronization code;
所述循环前缀模块用于加入循环前缀；The cyclic prefix module is used to add a cyclic prefix;
所述声音生成模块用于生成声音信号。The sound generating module is used for generating sound signals.
进一步地，所述的声波通信发送装置中，调制模块将所述数据单元按预设编码规则调制到M个载波上具体包括：Further, in the acoustic wave communication sending device, the modulating module modulates the data unit to M carriers according to the preset encoding rules, specifically including:
将数据单元按预设转换规则转换为一组复数序列，并按预设选取规则从该复数序列中选取M个复数，并将该M个复数与(N-M)个0以预设组成规则组成一长度为N的数据组，并对该数据组做N点傅里叶逆变换；其中N>M且N＝2i，i为正整数；Convert the data unit into a set of complex number sequences according to the preset conversion rules, and select M complex numbers from the complex number sequence according to the preset selection rules, and combine the M complex numbers and (NM) 0s into a set according to the preset composition rules A data group with a length of N, and performing an N-point Fourier inverse transform on the data group; where N>M and N=2i , i is a positive integer;
连接所有傅里叶逆变换结果信号得到调制结果信号。Concatenate all inverse Fourier transform result signals to obtain the modulated result signal.
进一步地，所述的声波通信发送装置中，所述数据单元包括数据长度、分组数目或分组编号，并且数据长度、分组数目或分组编号的数值均小于或等于255。Further, in the acoustic wave communication sending device, the data unit includes data length, group number or group number, and the values of data length, group number or group number are all less than or equal to 255.
进一步地，所述的声波通信发送装置中，M的取值为2-64，且M个载波中任意两个载波的频率差值的绝对值范围为86Hz-16kHz。Further, in the acoustic wave communication sending device, the value of M is 2-64, and the absolute value range of the frequency difference between any two carriers among the M carriers is 86 Hz-16 kHz.
进一步地，所述的声波通信发送装置中，M的取值为2-16，且M个载波中任意两个载波的频率差值的绝对值范围为750Hz-3kHz。Further, in the acoustic wave communication sending device, the value of M is 2-16, and the absolute value range of the frequency difference between any two carriers among the M carriers is 750 Hz-3 kHz.
进一步地，所述的声波通信发送装置中，声音生成模块所生成的声音信号的频率位于下述范围：Further, in the described sound wave communication sending device, the frequency of the sound signal generated by the sound generating module is in the following range:
(93.75*0.9*k-93.75*1.1*k)Hz，(93.75*0.9*k-93.75*1.1*k)Hz,
(86.13*0.9*k-86.13*1.1*k)Hz，(86.13*0.9*k-86.13*1.1*k)Hz,
(78.13*0.9*k-78.13*1.1*k)Hz，(78.13*0.9*k-78.13*1.1*k)Hz,
(62.5*0.9*k-62.5*1.1*k)Hz，或(62.5*0.9*k-62.5*1.1*k)Hz, or
(43.1*0.9*k-43.1*1.1*k)Hz，其中k＝0,1,...,255。(43.1*0.9*k-43.1*1.1*k)Hz, where k=0,1,...,255.
区别于现有技术，上述技术方案使用方便，传输过程无需匹配，随用随传；传输安全，传输过程可通过调节扬声器音量来控制传输距离；抗干扰性强，采用OFDM调制技术，抗频率衰减，同时提高了系统的抗环境干扰能力；信号质量高、适应性强，衰减较弱，并可有效的提高各种终端设备的适应性，可灵活应用于具有麦克风和/或扬声器的终端设备上，包括Android、ios、windowsphone操作系统的移动终端和windows平台的PC等。Different from the existing technology, the above-mentioned technical solution is easy to use, no matching is required in the transmission process, and it can be transmitted as needed; the transmission is safe, and the transmission distance can be controlled by adjusting the volume of the speaker during the transmission process; strong anti-interference, using OFDM modulation technology, anti-frequency attenuation , while improving the system's ability to resist environmental interference; high signal quality, strong adaptability, weak attenuation, and can effectively improve the adaptability of various terminal equipment, and can be flexibly applied to terminal equipment with microphones and/or speakers , including mobile terminals with Android, ios, and windowsphone operating systems and PCs with windows platforms.
附图说明Description of drawings
图1为本发明一实施方式所述声波通信发送方法的流程图；FIG. 1 is a flow chart of the acoustic wave communication sending method according to an embodiment of the present invention;
图2为本发明一实施方式所述声波通信发送装置的结构示意图。Fig. 2 is a schematic structural diagram of the acoustic wave communication sending device according to an embodiment of the present invention.
附图标记说明：Explanation of reference signs:
21-数据拆分模块21-Data splitting module
22-校验设置模块22- Checksum setting module
23-调制模块23-modulation module
24-同步码模块24-synchronous code module
25-循环前缀模块25 - Cyclic Prefix Module
26-声音生成模块26 - Sound Generation Module
具体实施方式detailed description
为详细说明技术方案的技术内容、构造特征、所实现目的及效果，以下结合具体实施例并配合附图详予说明。In order to explain in detail the technical content, structural features, achieved goals and effects of the technical solution, the following will be described in detail in conjunction with specific embodiments and accompanying drawings.
请参阅图1，为本发明一实施方式所述声波通信发送方法的流程图；所述方法包括如下步骤：Please refer to FIG. 1, which is a flow chart of the acoustic wave communication sending method according to an embodiment of the present invention; the method includes the following steps:
S11、按预设长度条件拆分待发送数据，得到若干数据单元。S11. Split the data to be sent according to a preset length condition to obtain several data units.
在本步骤中，首先选择或编辑待发送的具体内容，计算待发送数据的长度，然后根据实际应用中系统的设置以不超过40个字节的长度对待发送数据进行拆分，得到若干数据单元。后续的数据处理都将以每一数据单元为单位分别进行。在待发送数据的原始长度本身就已符合预设长度条件时，本步骤可省去。In this step, first select or edit the specific content to be sent, calculate the length of the data to be sent, and then split the data to be sent with a length of no more than 40 bytes according to the system settings in the actual application to obtain several data units . Subsequent data processing will be carried out separately for each data unit. When the original length of the data to be sent already meets the preset length condition, this step can be omitted.
S12、对数据单元设置校验编码。S12. Set a check code for the data unit.
在本步骤中，首先对经拆分后的每一数据单元进行标记，再在数据单元的末端以1bit为单位设置于前端数据分组相对应的比特位。通过设置校验码，为接收端的数据解调提供冗余校错的依据。所述校验方式包括奇偶校验、奇偶差奇偶校验和CRC循环冗余校验，还可以是其他能达到数据校验目的的常规方法。In this step, each split data unit is first marked, and then the corresponding bit of the front data packet is set at the end of the data unit in units of 1 bit. By setting the check code, it provides the basis for redundant error correction for the data demodulation at the receiving end. The check method includes parity check, parity difference parity check and CRC cyclic redundancy check, and can also be other conventional methods that can achieve the purpose of data check.
S13、将所述数据单元按预设编码规则调制到M个载波上。S13. Modulate the data unit onto M carriers according to a preset coding rule.
本步骤具体包括：This step specifically includes:
将数据单元按预设转换规则转换为一组复数序列，并按预设选取规则从该复数序列中选取M个复数，并将该M个复数与(N-M)个0以预设组成规则组成一长度为N的数据组，并对该数据组做N点傅里叶逆变换；其中N>M且N＝2i，i为正整数；Convert the data unit into a set of complex number sequences according to the preset conversion rules, and select M complex numbers from the complex number sequence according to the preset selection rules, and combine the M complex numbers and (NM) 0s into a set according to the preset composition rules A data group with a length of N, and performing an N-point Fourier inverse transform on the data group; where N>M and N=2i , i is a positive integer;
连接所有傅里叶逆变换结果信号得到调制结果信号。Concatenate all inverse Fourier transform result signals to obtain the modulated result signal.
所述预设转换规则可以是BPSK或QPSK。若采用BPSK转换，则将数字序列中的“0”调制为“-1”，数字序列中的“1”调制为“1”，从而得到正负交错的BPSK信号；若采用QPSK转换，则将序列中的“00”调制为“-1-i”，“01”调制为“-1+i”，“10”调制为“1-i”，“11”调制为“1+i”，从而得到四个相位的QPSK数据流，方便后续数据的载波调制，为数据传输提供保障。The preset conversion rule may be BPSK or QPSK. If BPSK conversion is used, the "0" in the digital sequence is modulated into "-1", and the "1" in the digital sequence is modulated into "1", so as to obtain positive and negative interleaved BPSK signals; if QPSK conversion is used, the "00" in the sequence is modulated as "-1-i", "01" is modulated as "-1+i", "10" is modulated as "1-i", and "11" is modulated as "1+i", thus The QPSK data stream of four phases is obtained, which facilitates the carrier modulation of subsequent data and provides guarantee for data transmission.
所述预设选取规则可以包括从所述复数序列中选取M个复数的起始位置或选取规律，例如从复数序列i1-i10中选出3个复数，可以是i1,i2,i3，可以是i5,i6,i7,可以是i4,i8,i10，也可以是i9,i3,i7。The preset selection rule may include the starting position or selection rule for selecting M complex numbers from the complex number sequence, for example, selecting 3 complex numbers from the complex number sequence i1 -i10 , which may be i1 , i2 , i3 can be i5 , i6 , i7 , i4 , i8 , i10 , or i9 , i3 , i7 .
所述预设组成规则包括所述(N-M)个0在长度为N的数据组中的位置，例如该(N-M)个0位于长度为N的数据组的前端，位于长度为N的数据组的后端，或位于长度为N的数据组的中间。The preset composition rule includes the position of the (N-M) 0s in the data group with a length of N, for example, the (N-M) 0s are located at the front end of the data group with a length of N, and at the end of the data group with a length of N. Backend, or in the middle of a data group of length N.
优选的预设组成规则为将该(N-M)个0置于长度为N的数据组的中间。例如，当N＝10，M＝6时，0的数目为4，按照所述优选的组成规则，该长度为N的数据组排列方式为：a1,a2,a3,0,0,0,0,a4,a5,a6,。其中a1-a6为有效数据。这种优选组成规则的有益之处在于，实际操作中，部分fft变换得到的结果特征为中间是最大正频率值和负频率值，两头为0；而将0置于中间，则处理效果相当于取了连续的-L-+L频率值，再经过搬移到0-22k频段的操作后，可以得到一个连续的频率。A preferred preset composition rule is to place the (NM) 0s in the middle of a data group with a length of N. For example, when N=10, M=6, the number of 0 is 4, according to the preferred composition rule, the arrangement of the data group with length N is: a1 , a2 , a3 ,0,0, 0,0,a4 ,a5 ,a6 ,. Among them, a1 -a6 are valid data. The benefit of this optimal composition rule is that in actual operation, the result obtained by partial fft transformation is characterized by the maximum positive frequency value and negative frequency value in the middle, and 0 at both ends; and if 0 is placed in the middle, the processing effect is equivalent to After taking the continuous -L-+L frequency value, and then moving to the 0-22k frequency band, a continuous frequency can be obtained.
本实施方式中的调制本质上是OFDM调制，其过程中使用了128个子载波(即N＝128)，载波间隔Δf＝375Hz，有效子载波数为8(即M＝8)，有效符号持续时间T＝2.67ms，信号带宽f＝3k。The modulation in this embodiment is OFDM modulation in essence, used 128 subcarriers (namely N=128) in its process, carrier spacing Δf=375Hz, effective subcarrier number is 8 (namely M=8), effective symbol duration T=2.67ms, signal bandwidth f=3k.
OFDM的主要实现过程是基于傅里叶变换与逆变换。本步骤中在傅里叶逆变换操作之前还包括一预处理操作，变换之后还包括一后处理操作。具体为：The main implementation process of OFDM is based on Fourier transform and inverse transform. In this step, a pre-processing operation is also included before the inverse Fourier transform operation, and a post-processing operation is also included after the transform. Specifically:
对一数据单元，以一个字节为单位进行串并转换，即将每个字节的8bit数据分为前后4bit，在这中间加入120个0作为冗余数据构成128个bit的一组数据，然后对这组包含128个bit的数据进行快速傅里叶逆变换，得到频域数据，待所有的分组数据都完成了频域转换后，再将各组数据还原，将并行数据转换为串行的数据流，即将得到的各分组频域数据按照原先的顺序组合为一整串的数据流，从而完成OFDM调制。上述的每个字节的8bit即为构成有效子载波的实际数据来源，在数据流传输过程中占据了T＝2.67ms的传输时间；加入的120个0，即增加了120bit的0是为了防止数据的频域混叠，在数据流传输过程中构成了Δf＝375Hz的载波间隔，可以有效的分隔数据字节。For a data unit, serial-to-parallel conversion is performed in units of one byte, that is, the 8-bit data of each byte is divided into 4 bits before and after, and 120 0s are added in the middle as redundant data to form a set of 128-bit data, and then Fast Fourier inverse transform is performed on this group of data containing 128 bits to obtain frequency domain data. After all grouped data have completed frequency domain conversion, each group of data is restored, and parallel data is converted into serial The data stream, that is, the frequency domain data of each packet to be obtained is combined into a whole series of data streams according to the original sequence, so as to complete the OFDM modulation. The above-mentioned 8 bits of each byte are the actual data sources constituting the effective subcarriers, which occupy the transmission time of T=2.67ms during the data stream transmission process; the 120 0s added, that is, the 120 bits of 0s are added to prevent The frequency domain aliasing of data constitutes a carrier interval of Δf=375Hz during data stream transmission, which can effectively separate data bytes.
优选地，M的取值为2-64，且M个载波中任意两个载波的频率差值的绝对值范围为86Hz-16kHz。Preferably, the value of M is 2-64, and the absolute value range of the frequency difference between any two carriers among the M carriers is 86 Hz-16 kHz.
更优选地，M的取值为2-16，且M个载波中任意两个载波的频率差值的绝对值范围为750Hz-3kHz。More preferably, the value of M is 2-16, and the absolute value range of the frequency difference between any two carriers among the M carriers is 750 Hz-3 kHz.
对于上述两个优选方案，以单路信号码率为K、M取2为例进行说明：此时传输速率可以认为是2K，但随着M的提高，需要减少K值才能保持稳定性，这样总速率K*M并不完全正比于M。同时随着M增大，计算复杂性也随之增加。For the above two preferred solutions, take the code rate of a single signal as K and M as an example to illustrate: at this time, the transmission rate can be considered as 2K, but with the increase of M, the value of K needs to be reduced to maintain stability. The total rate K*M is not exactly proportional to M. At the same time, as M increases, the computational complexity also increases.
M取2时，相当于串并转换以2个bit为单位，分为前后各1bit，在这中间加入126个0构成128个bit的一组数据的技术效果在于，比单路传输提高了近一倍的传输速率，估计可以达到1.2kbps(当采取BPSK调制时)。When M is 2, it is equivalent to serial-to-parallel conversion with 2 bits as the unit, divided into 1 bit before and after, and adding 126 0s in the middle to form a set of 128-bit data. The technical effect is that it improves nearly Double the transmission rate, it is estimated that it can reach 1.2kbps (when BPSK modulation is adopted).
M取16时，相当于以两个字节16bit为单位，前后各8bit，中间112个0。其技术效果在于，在移动设备等计算能力较差的计算环境中，能够流畅运行，并且保证了较高的传输速率，理论可以达到4.8kbps。When M is 16, it is equivalent to using two bytes of 16 bits as a unit, 8 bits before and after, and 112 0s in the middle. Its technical effect is that it can run smoothly in a computing environment with poor computing power such as mobile devices, and ensure a high transmission rate, which can theoretically reach 4.8kbps.
M取32时，相当于以4个字节32bit为单位，前后各16bit，中间96个0。其技术效果在于，比M取2或16的方案的传输速率都高，并且在声音传输时比较稳定，适用于诸如iphone等声音设备性能较好的实用场景，理论传输速率可以达到9.6kbps。When M is 32, it is equivalent to taking 4 bytes of 32bit as the unit, 16bits before and after, and 96 zeros in the middle. Its technical effect is that the transmission rate is higher than that of the scheme where M is 2 or 16, and it is relatively stable in sound transmission. It is suitable for practical scenarios with better performance of sound equipment such as iphone, and the theoretical transmission rate can reach 9.6kbps.
M取64时，相当于以8个字节64bit为单位，前后各32bit，中间64个0。在几种方案中传输速率最高，适用于定制高端麦克风的硬件设备，理论传输速率可以达到19.2kbps。When M is 64, it is equivalent to taking 8 bytes of 64bit as the unit, 32bits before and after, and 64 0s in the middle. The transmission rate is the highest among several solutions, and it is suitable for customizing the hardware equipment of high-end microphones. The theoretical transmission rate can reach 19.2kbps.
M个载波中任意两个载波的频率差值的绝对值范围实质上与M有关。例如，在3kHz以上，再取3kHz的频率差值范围(实际频谱3kHz-6kHz)，一般手机都能平稳接收，此时，当M＝8时，正好得到最小间隔375Hz。对于一些高端手机，6-8kHz左右的频谱范围是能够接收到的，此时如果M＝8，频率差值绝对值最大值取6kHz，最小间隔正好为750Hz。16kHz是一些特别定制的硬件设备可以达到的范围。The range of the absolute value of the frequency difference between any two carriers among the M carriers is substantially related to M. For example, above 3kHz, the frequency difference range of 3kHz (the actual frequency spectrum is 3kHz-6kHz) is taken, and the general mobile phone can receive stably. At this time, when M=8, the minimum interval of 375Hz is just obtained. For some high-end mobile phones, the spectrum range of about 6-8kHz can be received. At this time, if M=8, the maximum absolute value of the frequency difference is 6kHz, and the minimum interval is exactly 750Hz. 16kHz is the range that some specially customized hardware devices can achieve.
频率差最小值86Hz，是M取64，最大频率差为5504时的取值。The minimum frequency difference is 86Hz, which is the value when M is 64 and the maximum frequency difference is 5504.
S14、在数据单元中加入同步码。S14. Add a synchronization code to the data unit.
即在每个数据分组的前端加入7个OFDM符号组成的同步码，同步码按照一定的规律排列，主要用于接收数据时的信号同步，符号格式为：That is, a synchronization code consisting of 7 OFDM symbols is added to the front end of each data packet. The synchronization code is arranged according to a certain rule and is mainly used for signal synchronization when receiving data. The symbol format is:
P＝[1,0,1,0,-1,0,1,0]；P=[1,0,1,0,-1,0,1,0];
-P＝[-1,0,-1,0,1,0,-1,0]；-P=[-1,0,-1,0,1,0,-1,0];
1＝[1,1,1,1,1,1,1,1]。1 = [1,1,1,1,1,1,1,1].
同步码的使用，主要是为了接收端在数据解调的时候，作为数据同步、信道估计等的依据，同时也增加了数据的一定冗余度和健壮性。The use of synchronization codes is mainly for data synchronization and channel estimation at the receiving end when demodulating data, and also increases the redundancy and robustness of data.
同步码的结构由7个OFDM符号组成，7个符号分别为[1,0,1,0，-1，0,1,0]，[1,0,1,0，-1，0,1,0]，[-1,0,-1,0，1，0,-1,0]，[-1,0,-1,0，1，0,-1,0]，[1,0,1,0，-1，0,1,0]，[1,0,1,0，-1，0,1,0]，[1,1,1,1,1,1,1,1]，即组成了“P，P，-P，-P，P，P，1”的序列。The structure of the synchronization code consists of 7 OFDM symbols, and the 7 symbols are [1,0,1,0,-1,0,1,0], [1,0,1,0,-1,0,1 ,0], [-1,0,-1,0,1,0,-1,0],[-1,0,-1,0,1,0,-1,0],[1,0 ,1,0,-1,0,1,0], [1,0,1,0,-1,0,1,0], [1,1,1,1,1,1,1,1 ], which constitutes the sequence of "P, P, -P, -P, P, P, 1".
在其他实施方式中，同步码的加入也可以在生成声音信号之前的任何时候进行，并不一定如本实施方式所述在步骤“将所述数据单元按预设编码规则调制到M个载波上”之后以及步骤“加入循环前缀”之前。In other embodiments, the addition of the synchronization code can also be performed at any time before the sound signal is generated, not necessarily in the step "modulate the data unit onto the M carriers according to the preset coding rule as described in this embodiment." " and before the step "Join cyclic prefix".
进一步地，数据单元包括同步码、数据长度、分组数目、分组编号或实际数据。其中数据长度、分组数目或分组编号的数值均小于或等于255。Further, the data unit includes synchronization code, data length, group number, group number or actual data. The values of the data length, the number of groups or the number of groups are all less than or equal to 255.
其中，同步码FCH主要用于接收端对数据的同步和信道估计判断；一个字节长度的数据说明了发送端实际应该发送的数据的长度；分组数指明了发送数据的总的分组数量；分组编号指明了本数据分组的分组编号，用于说明本分组数据所处的实际位置，用于接收端对数据进行排列还原；传输的分组的实际数据部分，数据部分保存了每一组的实际数据内容。通过上述分组的有机组合，接收端可以有效的解调还原出发送端所发送的数据，并具有相应的校错能力。Among them, the synchronization code FCH is mainly used for the data synchronization and channel estimation judgment of the receiving end; the data of a byte length indicates the length of the data that the sending end should actually send; the number of packets indicates the total number of packets to send data; The number indicates the group number of this data group, which is used to explain the actual location of the group data, and is used by the receiving end to arrange and restore the data; the actual data part of the transmitted group, the data part saves the actual data of each group content. Through the organic combination of the above packets, the receiving end can effectively demodulate and restore the data sent by the sending end, and has a corresponding error correction capability.
经分组后的每个数据单元包括了7个OFDM符号长度的同步码+1字节的数据长度+1字节的分组数+1字节的分组编号+分组的实际数据部分。此外分组的参数具体为：Each data unit after grouping includes a synchronization code of 7 OFDM symbol length + 1 byte data length + 1 byte group number + 1 byte group number + the actual data part of the group. In addition, the grouping parameters are as follows:
每组最大长度：40个OFDM符号为40byte；The maximum length of each group: 40 OFDM symbols are 40byte;
每组最大总比特数：40×8＝320bit。The maximum total number of bits per group: 40×8=320bit.
对分组长度范围进行限制的理由是，在具体实施过程中为了简化通信系统，没有考虑OFDM系统的采样频率同步和载波频率同步，因此数据传输的长度不能太长，否则会由于误差累加造成误码。同时数据在传输过程中容易受到干扰而误码，因此使用分组传输。经过大量实际测量，分组长度为(20～80个)符号时，系统的效率最高，其他长度也可以接受，但至少要小于240个符号，否则会因为误码的影响，很难成功接收。常规通信方法中的分组长度一般比较长或无限制，可能导致最终声音不稳定。本实施方式通过对分组长度进行限制，达到了稳定可靠的传输效果。The reason for restricting the range of packet lengths is that in order to simplify the communication system in the specific implementation process, the sampling frequency synchronization and carrier frequency synchronization of the OFDM system are not considered, so the length of data transmission cannot be too long, otherwise it will cause bit errors due to error accumulation . At the same time, data is susceptible to interference and bit errors during transmission, so packet transmission is used. After a large number of actual measurements, the system has the highest efficiency when the packet length is (20-80) symbols, and other lengths are also acceptable, but at least less than 240 symbols, otherwise it will be difficult to receive successfully due to the influence of bit errors. The packet length in conventional communication methods is generally long or unlimited, which may lead to unstable final sound. In this embodiment, a stable and reliable transmission effect is achieved by limiting the packet length.
S15、在数据单元中加入循环前缀。S15. Add a cyclic prefix to the data unit.
在完成数据的OFDM调制后会得到128bit为单位的连续数据流，此时将每个128bit重新整合，将其中的后32bit复制添加到128bit流的前端，构成160bit的连续数据流，完成数据的循环，即实现了循环前缀的添加。After the OFDM modulation of the data is completed, a continuous data stream of 128bit will be obtained. At this time, each 128bit will be reintegrated, and the last 32bit copy will be added to the front end of the 128bit stream to form a 160bit continuous data stream to complete the cycle of data. , which implements the addition of a cyclic prefix.
S16、生成声音信号。S16. Generate a sound signal.
通过此步，将上述编码调制后的数据流再调制到可以传输的频带上，生成声音信号。其具体参数为：根据采样定理，采用不低于数据频率2倍的采样频率对数据流进行采样，为了较好的对数据采样，可采用不低于48kHz的采样频率，然后使用普通手机的麦克风和扬声器可接收较好的频率f＝3～7KHz作为载波频率，接着将采样得到的数据与载波信号相乘得到频带传输数据，即完成了数据的频带调制，从而得到可供声音传输的音频数据流。本步骤中所生成的声音信号的频率位于下述范围：Through this step, the above coded and modulated data stream is modulated to a frequency band that can be transmitted to generate a sound signal. The specific parameters are: according to the sampling theorem, the data stream is sampled at a sampling frequency not lower than twice the data frequency. In order to better sample the data, a sampling frequency not lower than 48kHz can be used, and then the microphone of an ordinary mobile phone can be used And the speaker can receive a better frequency f = 3 ~ 7KHz as the carrier frequency, and then multiply the sampled data by the carrier signal to obtain the frequency band transmission data, that is, the frequency band modulation of the data is completed, so as to obtain audio data for sound transmission flow. The frequency of the sound signal generated in this step is in the following range:
(93.75*0.9*k-93.75*1.1*k)Hz，(93.75*0.9*k-93.75*1.1*k)Hz,
(86.13*0.9*k-86.13*1.1*k)Hz，(86.13*0.9*k-86.13*1.1*k)Hz,
(78.13*0.9*k-78.13*1.1*k)Hz，(78.13*0.9*k-78.13*1.1*k)Hz,
(62.5*0.9*k-62.5*1.1*k)Hz，或(62.5*0.9*k-62.5*1.1*k)Hz, or
(43.1*0.9*k-43.1*1.1*k)Hz，其中k＝0,1,...,255。(43.1*0.9*k-43.1*1.1*k)Hz, where k=0,1,...,255.
令生成的声音信号位于上述范围频率时，正好可以在两个普通录音设备的常用采样率范围取得正交性。例如，在48k采样率下，取第一组频率中任意两个都可以构成两两正交的关系。When the generated sound signal is placed in the frequency range mentioned above, the orthogonality can be obtained just in the commonly used sampling rate range of two common recording devices. For example, at a sampling rate of 48k, any two frequencies in the first group can form a pairwise orthogonal relationship.
发明人在选择信号频率范围的过程中发现，由于一般手机的喇叭可以播放的频率范围为(0～22KHz)信号，手机麦克风可以录制的频率范围为(0～22KHz)，部分手机的麦克风可以录制的频率范围为(0～9KHz)(已知的手机有小米1，努比亚手机)，在(0～3KHz)频率范围内，信号很容易受到环境噪声的影响，比如人说话的声音等。因此可以使用的频率范围为(3KHz～22KHz)。此外发明人经过测试发现，16KHz以上的信号在手机播放和接收过程中被衰减的很严重，因此不适用于传输数据，因此可以使用的频率范围为(3KHz～16KHz)。如果想要兼容所有手机，那么可以使用的频率范围为(3KHz～9KHz)。In the process of selecting the frequency range of the signal, the inventor found that since the speaker of a general mobile phone can play the signal in the frequency range of (0-22KHz), the microphone of the mobile phone can record the frequency range of (0-22KHz), and the microphone of some mobile phones can record The frequency range of the signal is (0-9KHz) (known mobile phones include Mi 1 and Nubia mobile phones). In the frequency range of (0-3KHz), the signal is easily affected by environmental noise, such as the voice of people talking. Therefore, the frequency range that can be used is (3KHz～22KHz). In addition, the inventor found through tests that the signals above 16KHz are seriously attenuated during the playback and reception of mobile phones, so they are not suitable for data transmission, so the usable frequency range is (3KHz～16KHz). If you want to be compatible with all mobile phones, the frequency range that can be used is (3KHz ~ 9KHz).
此外，经发明人研究发现，基于声音在空气中传播的衰减公式可知，衰减主要包括发射衰减和空气吸收两部分；在一般室温和相对湿度条件下，传输距离一定时，22kHz以上频率的声音传输衰减率急剧增加，因此M个载波中任意两个载波的频率差值的绝对值应小于或等于22kHz，否则在进行频谱搬移过程中会使得声波最高频率超过22kHz。考虑到一定环境噪声的存在，为维持信噪比，16kHz为较乐观的估计值；当环境噪声较大时，3kHz左右具有较强的鲁棒性。In addition, the inventors found that based on the attenuation formula of sound propagating in the air, the attenuation mainly includes two parts: emission attenuation and air absorption; The attenuation rate increases sharply, so the absolute value of the frequency difference between any two carriers among the M carriers should be less than or equal to 22kHz, otherwise the highest frequency of the sound wave will exceed 22kHz during the spectrum shifting process. Considering the existence of certain environmental noise, in order to maintain the signal-to-noise ratio, 16kHz is an optimistic estimate; when the environmental noise is large, around 3kHz has strong robustness.
发明人经过大量的实际测试得到子载波间隔Δf为(86HZ～750HZ)时,通信效果较佳。当低于86Hz时，各个子载波间容易发生频谱干扰，造成误码率提高。当高于750Hz时，频谱的利用率较低，传输码率难以提高。有效子载波数N的值可以由信号带宽f和子载波间隔Δf得到，N＝f/Δf。The inventor obtained through a large number of actual tests that when the subcarrier spacing Δf is (86HZ～750HZ), the communication effect is better. When it is lower than 86 Hz, spectrum interference is likely to occur between subcarriers, resulting in an increase in the bit error rate. When it is higher than 750Hz, the spectrum utilization rate is low, and it is difficult to increase the transmission code rate. The value of the effective subcarrier number N can be obtained from the signal bandwidth f and the subcarrier spacing Δf, N=f/Δf.
进一步地，步骤S13中，为了提高码率，同时使用多个载波信号传输数据。为了避免载波间相互混叠，选取相互正交的载波信号。这些相互正交的子载波满足以下公式：
其中Tsym表示信号周期。在48kHz采样频率下可以选择的正交频率有表1所示的频率。可以根据实际需求选择频率1、频率2、频率3或频率4中的几个或全部频率点。where Tsym represents the signal period. The quadrature frequencies that can be selected under the 48kHz sampling frequency are those shown in Table 1. Several or all frequency points in frequency 1, frequency 2, frequency 3 or frequency 4 can be selected according to actual needs.
表1采样频率48kHz时可以选用的正交频率(单位Hz)Table 1 The quadrature frequencies that can be selected when the sampling frequency is 48kHz (unit Hz)
又例如，在44.1kHz采样频率下可以选择的正交频率有表2所示的频率。可以根据实际需求选择频率1、频率2、频率3或频率4中的几个或者全部频率点。For another example, the quadrature frequencies that can be selected at a sampling frequency of 44.1kHz are those shown in Table 2. Several or all frequency points in frequency 1, frequency 2, frequency 3 or frequency 4 can be selected according to actual needs.
表2采样频率44.1kHz时可以选用的正交频率(单位Hz)Table 2 The quadrature frequencies that can be selected when the sampling frequency is 44.1kHz (unit Hz)
本实施方式设计的声波通信发送方法实现了对数据的快速、准确、高效的调制和发送，在采用BPSK调制的系统中最高可实现2.4kbps的传输速率，而在采用QPSK调制的系统中最高的传输速率可达到4.8kbps。The acoustic wave communication transmission method designed in this embodiment realizes fast, accurate and efficient modulation and transmission of data, and the highest transmission rate of 2.4kbps can be realized in the system adopting BPSK modulation, and the highest transmission rate in the system adopting QPSK modulation The transfer rate can reach 4.8kbps.
请参阅图2，为本发明一实施方式所述声波通信发送装置的结构示意图；所述装置包括数据拆分模块21、校验设置模块22、调制模块23、同步码模块24、循环前缀模块25和声音生成模块26。Please refer to FIG. 2, which is a schematic structural diagram of the acoustic wave communication sending device according to an embodiment of the present invention; the device includes a data splitting module 21, a verification setting module 22, a modulation module 23, a synchronization code module 24, and a cyclic prefix module 25 and sound generation module 26 .
所述数据拆分模块21用于按预设长度条件拆分待发送数据，得到若干数据单元。The data splitting module 21 is used to split the data to be sent according to preset length conditions to obtain several data units.
所述校验设置模块22用于对数据单元设置校验编码。The check setting module 22 is used to set a check code for the data unit.
所述调制模块23用于将所述数据单元按预设编码规则调制到M个载波上，M为大于或等于2的正整数，所述M个载波满足两两正交的关系，且M个载波中任意两个载波的频率差值的绝对值小于或等于22kHz；所述编码规则包括相位参数或幅度参数；具体包括：The modulation module 23 is used to modulate the data unit onto M carriers according to a preset coding rule, where M is a positive integer greater than or equal to 2, and the M carriers satisfy a pairwise orthogonal relationship, and the M The absolute value of the frequency difference between any two carriers in the carrier is less than or equal to 22kHz; the coding rules include phase parameters or amplitude parameters; specifically include:
将数据单元按预设转换规则转换为一组复数序列，并按预设选取规则从该复数序列中选取M个复数，并将该M个复数与(N-M)个0以预设组成规则组成一长度为N的数据组，并对该数据组做N点傅里叶逆变换；其中N>M且N＝2i，i为正整数。Convert the data unit into a set of complex number sequences according to the preset conversion rules, and select M complex numbers from the complex number sequence according to the preset selection rules, and combine the M complex numbers and (NM) 0s into a set according to the preset composition rules A data group with a length of N, and N-point inverse Fourier transform is performed on the data group; where N>M and N=2i , i is a positive integer.
连接所有傅里叶逆变换结果信号得到调制结果信号。Concatenate all inverse Fourier transform result signals to obtain the modulated result signal.
所述同步码模块24用于加入同步码。The synchronization code module 24 is used for adding synchronization codes.
所述循环前缀模块25用于加入循环前缀。The cyclic prefix module 25 is used to add a cyclic prefix.
所述声音生成模块用于生成声音信号。The sound generating module is used for generating sound signals.
本装置实现声波通信发送功能的具体方式如下：The specific way for this device to realize the sending function of acoustic wave communication is as follows:
首先，数据拆分模块21用于按预设长度条件拆分待发送数据，得到若干数据单元。数据拆分模块21首先选择或编辑待发送的具体内容，计算待发送数据的长度，然后根据实际应用中系统的设置以不超过40个字节的长度对待发送数据进行拆分，得到若干数据单元。后续的数据处理都将以每一数据单元为单位分别进行。在待发送数据的原始长度本身就已符合预设长度条件时。数据拆分模块21及其所执行的功能可省去。First, the data splitting module 21 is used to split the data to be sent according to preset length conditions to obtain several data units. The data splitting module 21 first selects or edits the specific content to be sent, calculates the length of the data to be sent, and then splits the data to be sent with a length of no more than 40 bytes according to the system settings in practical applications to obtain several data units . Subsequent data processing will be carried out separately for each data unit. When the original length of the data to be sent already meets the preset length condition. The data splitting module 21 and the functions it executes can be omitted.
校验设置模块22用于对一数据单元设置校验编码。The check setting module 22 is used to set a check code for a data unit.
首先校验设置模块22对每一数据单元进行标记，再在数据单元的末端以1bit为单位设置于前端数据分组相对应的比特位。通过设置校验码，为接收端的数据解调提供冗余校错的依据。所述校验方式包括奇偶校验、奇偶差奇偶校验和CRC循环冗余校验，还可以是其他能达到数据校验目的的常规方法。First, the check setting module 22 marks each data unit, and then sets the corresponding bit in the front data packet at the end of the data unit in units of 1 bit. By setting the check code, it provides the basis for redundant error correction for the data demodulation at the receiving end. The check method includes parity check, parity difference parity check and CRC cyclic redundancy check, and can also be other conventional methods that can achieve the purpose of data check.
调制模块23用于将所述数据单元按预设编码规则调制到M个载波上。具体包括：The modulation module 23 is used to modulate the data unit onto M carriers according to a preset coding rule. Specifically include:
将数据单元按预设转换规则转换为一组复数序列，并按预设选取规则从该复数序列中选取M个复数，并将该M个复数与(N-M)个0以预设组成规则组成一长度为N的数据组，并对该数据组做N点傅里叶逆变换；其中N>M且N＝2i，i为正整数；Convert the data unit into a set of complex number sequences according to the preset conversion rules, and select M complex numbers from the complex number sequence according to the preset selection rules, and combine the M complex numbers and (NM) 0s into a set according to the preset composition rules A data group with a length of N, and performing an N-point Fourier inverse transform on the data group; where N>M and N=2i , i is a positive integer;
连接所有傅里叶逆变换结果信号得到调制结果信号。Concatenate all inverse Fourier transform result signals to obtain the modulated result signal.
所述预设转换规则可以是BPSK或QPSK。若采用BPSK转换，则将数字序列中的“0”调制为“-1”，数字序列中的“1”调制为“1”，从而得到正负交错的BPSK信号；若采用QPSK转换，则将序列中的“00”调制为“-1-i”，“01”调制为“-1+i”，“10”调制为“1-i”，“11”调制为“1+i”，从而得到四个相位的QPSK数据流，方便后续数据的载波调制，为数据传输提供保障。The preset conversion rule may be BPSK or QPSK. If BPSK conversion is used, the "0" in the digital sequence is modulated into "-1", and the "1" in the digital sequence is modulated into "1", so as to obtain positive and negative interleaved BPSK signals; if QPSK conversion is used, the "00" in the sequence is modulated as "-1-i", "01" is modulated as "-1+i", "10" is modulated as "1-i", and "11" is modulated as "1+i", thus The QPSK data stream of four phases is obtained, which facilitates the carrier modulation of subsequent data and provides guarantee for data transmission.
所述预设选取规则可以包括从所述复数序列中选取M个复数的起始位置或选取规律，例如从复数序列i1-i10中选出3个复数，可以是i1,i2,i3，可以是i5,i6,i7,可以是i4,i8,i10，也可以是i9,i3,i7。The preset selection rule may include the starting position or selection rule for selecting M complex numbers from the complex number sequence, for example, selecting 3 complex numbers from the complex number sequence i1 -i10 , which may be i1 , i2 , i3 can be i5 , i6 , i7 , i4 , i8 , i10 , or i9 , i3 , i7 .
所述预设组成规则包括所述(N-M)个0在长度为N的数据组中的位置，例如该(N-M)个0位于长度为N的数据组的前端，位于长度为N的数据组的后端，或位于长度为N的数据组的中间。The preset composition rule includes the position of the (N-M) 0s in the data group with a length of N, for example, the (N-M) 0s are located at the front end of the data group with a length of N, and at the end of the data group with a length of N. Backend, or in the middle of a data group of length N.
优选的预设组成规则为将该(N-M)个0置于长度为N的数据组的中间。例如，当N＝10，M＝6时，0的数目为4，按照所述优选的组成规则，该长度为N的数据组排列方式为：a1,a2,a3,0,0,0,0,a4,a5,a6,。其中a1-a6为有效数据。这种优选组成规则的有益之处在于，实际操作中，部分fft变换得到的结果特征为中间是最大正频率值和负频率值，两头为0；而将0置于中间，则处理效果相当于取了连续的-L-+L频率值，再经过搬移到0-22k频段的操作后，可以得到一个连续的频率。A preferred preset composition rule is to place the (NM) 0s in the middle of a data group with a length of N. For example, when N=10, M=6, the number of 0 is 4, according to the preferred composition rule, the arrangement of the data group with length N is: a1 , a2 , a3 ,0,0, 0,0,a4 ,a5 ,a6 ,. Among them, a1 -a6 are valid data. The benefit of this optimal composition rule is that in actual operation, the result obtained by partial fft transformation is characterized by the maximum positive frequency value and negative frequency value in the middle, and 0 at both ends; and if 0 is placed in the middle, the processing effect is equivalent to After taking the continuous -L-+L frequency value, and then moving to the 0-22k frequency band, a continuous frequency can be obtained.
调制模块23所进行的调制本质上是OFDM调制，其过程中使用了128个子载波(即N＝128)，载波间隔Δf＝375Hz，有效子载波数为8(即M＝8)，有效符号持续时间T＝2.67ms，信号带宽f＝3k。The modulation carried out by the modulation module 23 is OFDM modulation in nature, and 128 subcarriers (i.e. N=128) are used in the process, the carrier spacing Δf=375Hz, the effective number of subcarriers is 8 (i.e. M=8), and the effective symbols last Time T=2.67ms, signal bandwidth f=3k.
OFDM的主要实现过程是基于傅里叶变换与逆变换。在进行傅里叶逆变换操作之前调制模块23还需要进行一预处理操作，变换之后还包括一后处理操作。具体为：The main implementation process of OFDM is based on Fourier transform and inverse transform. The modulation module 23 also needs to perform a pre-processing operation before performing the inverse Fourier transform operation, and a post-processing operation after the transform. Specifically:
对一数据单元，以一个字节为单位进行串并转换，即将每个字节的8bit数据分为前后4bit，在这中间加入120个0作为冗余数据构成128个bit的一组数据，然后对这组包含128个bit的数据进行快速傅里叶逆变换，得到频域数据，待所有的分组数据都完成了频域转换后，再将各组数据还原，将并行数据转换为串行的数据流，即将得到的各分组频域数据按照原先的顺序组合为一整串的数据流，从而完成OFDM调制。上述的每个字节的8bit即为构成有效子载波的实际数据来源，在数据流传输过程中占据了T＝2.67ms的传输时间；加入的120个0，即增加了120bit的0是为了防止数据的频域混叠，在数据流传输过程中构成了Δf＝375Hz的载波间隔，可以有效地分隔数据字节。For a data unit, serial-to-parallel conversion is performed in units of one byte, that is, the 8-bit data of each byte is divided into 4 bits before and after, and 120 0s are added in the middle as redundant data to form a set of 128-bit data, and then Fast Fourier inverse transform is performed on this group of data containing 128 bits to obtain frequency domain data. After all grouped data have completed frequency domain conversion, each group of data is restored, and parallel data is converted into serial The data stream, that is, the frequency domain data of each packet to be obtained is combined into a whole series of data streams according to the original sequence, so as to complete the OFDM modulation. The above-mentioned 8 bits of each byte are the actual data sources constituting the effective subcarriers, which occupy the transmission time of T=2.67ms during the data stream transmission process; the 120 0s added, that is, 120 bits of 0s are added to prevent The frequency domain aliasing of data constitutes a carrier interval of Δf=375Hz during data stream transmission, which can effectively separate data bytes.
优选地，M的取值为2-64，且M个载波中任意两个载波的频率差值的绝对值范围为86Hz-16kHz。Preferably, the value of M is 2-64, and the absolute value range of the frequency difference between any two carriers among the M carriers is 86 Hz-16 kHz.
更优选地，M的取值为2-16，且M个载波中任意两个载波的频率差值的绝对值范围为750Hz-3kHz。More preferably, the value of M is 2-16, and the absolute value range of the frequency difference between any two carriers among the M carriers is 750 Hz-3 kHz.
对于上述两个优选方案，以单路信号码率为K、M取2为例进行说明：此时传输速率可以认为是2K，但随着M的提高，需要减少K值才能保持稳定性，这样总速率K*M并不完全正比于M。同时随着M增大，计算复杂性也随之增加。For the above two preferred solutions, take the code rate of a single signal as K and M as an example to illustrate: at this time, the transmission rate can be considered as 2K, but with the increase of M, the value of K needs to be reduced to maintain stability. The total rate K*M is not exactly proportional to M. At the same time, as M increases, the computational complexity also increases.
M取2时，相当于串并转换以2个bit为单位，分为前后各1bit，在这中间加入126个0构成128个bit的一组数据的技术效果在于，比单路传输提高了近一倍的传输速率，估计可以达到1.2kbps(当采取BPSK调制时)。When M is 2, it is equivalent to serial-to-parallel conversion with 2 bits as the unit, divided into 1 bit before and after, and adding 126 0s in the middle to form a set of 128-bit data. Double the transmission rate, it is estimated that it can reach 1.2kbps (when BPSK modulation is adopted).
M取16时，相当于以两个字节16bit为单位，前后各8bit，中间112个0。其技术效果在于，在移动设备等计算能力较差的计算环境中，能够流畅运行，并且保证了较高的传输速率，理论可以达到4.8kbps。When M is 16, it is equivalent to using two bytes of 16 bits as a unit, 8 bits before and after, and 112 0s in the middle. Its technical effect is that it can run smoothly in a computing environment with poor computing power such as mobile devices, and ensure a high transmission rate, which can theoretically reach 4.8kbps.
M取32时，相当于以4个字节32bit为单位，前后各16bit，中间96个0。其技术效果在于，比M取2或16的方案的传输速率都高，并且在声音传输时比较稳定，适用于诸如iphone等声音设备性能较好的实用场景，理论传输速率可以达到9.6kbps。When M is 32, it is equivalent to taking 4 bytes of 32bit as the unit, 16bits before and after, and 96 zeros in the middle. Its technical effect is that the transmission rate is higher than that of the scheme where M is 2 or 16, and it is relatively stable in sound transmission. It is suitable for practical scenarios with better performance of sound equipment such as iphone, and the theoretical transmission rate can reach 9.6kbps.
M取64时，相当于以8个字节64bit为单位，前后各32bit，中间64个0。在几种方案中传输速率最高，适用于定制高端麦克风的硬件设备，理论传输速率可以达到19.2kbps。When M is 64, it is equivalent to taking 8 bytes of 64bit as the unit, 32bits before and after, and 64 0s in the middle. The transmission rate is the highest among several solutions, and it is suitable for customizing the hardware equipment of high-end microphones. The theoretical transmission rate can reach 19.2kbps.
M个载波中任意两个载波的频率差值的绝对值范围实质上与M有关。例如，在3kHz以上，再取3kHz的频率差值范围(实际频谱3kHz-6kHz)，一般手机都能平稳接收，此时，当M＝8时，正好得到最小间隔375Hz。对于一些高端手机，6-8kHz左右的频谱范围是能够接收到的，此时如果M＝8，频率差值绝对值最大值取6kHz，最小间隔正好为750Hz。16kHz是一些特别定制的硬件设备可以达到的范围。The range of the absolute value of the frequency difference between any two carriers among the M carriers is substantially related to M. For example, above 3kHz, the frequency difference range of 3kHz (the actual frequency spectrum is 3kHz-6kHz) is taken, and the general mobile phone can receive stably. At this time, when M=8, the minimum interval of 375Hz is just obtained. For some high-end mobile phones, the spectrum range of about 6-8kHz can be received. At this time, if M=8, the maximum absolute value of the frequency difference is 6kHz, and the minimum interval is exactly 750Hz. 16kHz is the range that some specially customized hardware devices can achieve.
频率差最小值86Hz，是M取64，最大频率差为5504时的取值。The minimum frequency difference is 86Hz, which is the value when M is 64 and the maximum frequency difference is 5504.
同步码模块24用于在数据单元中加入同步码。The synchronization code module 24 is used for adding a synchronization code into the data unit.
即在每个数据分组的前端加入7个OFDM符号组成的同步码，同步码按照一定的规律排列，主要用于接收数据时的信号同步，符号格式为：That is, a synchronization code consisting of 7 OFDM symbols is added to the front end of each data packet. The synchronization code is arranged according to a certain rule and is mainly used for signal synchronization when receiving data. The symbol format is:
P＝[1,0,1,0,-1,0,1,0]；P=[1,0,1,0,-1,0,1,0];
-P＝[-1,0,-1,0,1,0,-1,0]；-P=[-1,0,-1,0,1,0,-1,0];
1＝[1,1,1,1,1,1,1,1]。1 = [1,1,1,1,1,1,1,1].
同步码的使用，主要是为了接收端在数据解调的时候，作为数据同步、信道估计等的依据，同时也增加了数据的一定冗余度和健壮性。The use of synchronization codes is mainly for data synchronization and channel estimation at the receiving end when demodulating data, and also increases the redundancy and robustness of data.
同步码的结构由7个OFDM符号组成，7个符号分别为[1,0,1,0，-1，0,1,0]，[1,0,1,0，-1，0,1,0]，[-1,0,-1,0，1，0,-1,0]，[-1,0,-1,0，1，0,-1,0]，[1,0,1,0，-1，0,1,0]，[1,0,1,0，-1，0,1,0]，[1,1,1,1,1,1,1,1]，即组成了“P，P，-P，-P，P，P，1”的序列。The structure of the synchronization code consists of 7 OFDM symbols, and the 7 symbols are [1,0,1,0,-1,0,1,0], [1,0,1,0,-1,0,1 ,0], [-1,0,-1,0,1,0,-1,0],[-1,0,-1,0,1,0,-1,0],[1,0 ,1,0,-1,0,1,0], [1,0,1,0,-1,0,1,0], [1,1,1,1,1,1,1,1 ], which constitutes the sequence of "P, P, -P, -P, P, P, 1".
进一步地，数据单元包括同步码、数据长度、分组数目、分组编号或实际数据。其中数据长度、分组数目或分组编号的数值均小于或等于255。Further, the data unit includes synchronization code, data length, group number, group number or actual data. The values of the data length, the number of groups or the number of groups are all less than or equal to 255.
其中，同步码FCH主要用于接收端对数据的同步和信道估计判断；一个字节长度的数据说明了发送端实际应该发送的数据的长度；分组数指明了发送数据的总的分组数量；分组编号指明了本数据分组的分组编号，用于说明本分组数据所处的实际位置，用于接收端对数据进行排列还原；传输的分组的实际数据部分，数据部分保存了每一组的实际数据内容。通过上述分组的有机组合，接收端可以有效的解调还原出发送端所发送的数据，并具有相应的校错能力。Among them, the synchronization code FCH is mainly used for the data synchronization and channel estimation judgment of the receiving end; the data of a byte length indicates the length of the data that the sending end should actually send; the number of packets indicates the total number of packets to send data; The number indicates the group number of this data group, which is used to explain the actual location of the group data, and is used by the receiving end to arrange and restore the data; the actual data part of the transmitted group, the data part saves the actual data of each group content. Through the organic combination of the above packets, the receiving end can effectively demodulate and restore the data sent by the sending end, and has a corresponding error correction capability.
经分组后的每个数据单元包括了7个OFDM符号长度的同步码+1字节的数据长度+1字节的分组数+1字节的分组编号+分组的实际数据部分。此外分组的参数具体为：Each data unit after grouping includes a synchronization code of 7 OFDM symbol length + 1 byte data length + 1 byte group number + 1 byte group number + the actual data part of the group. In addition, the grouping parameters are as follows:
每组最大长度：40个OFDM符号为40byte；The maximum length of each group: 40 OFDM symbols are 40byte;
每组最大总比特数：40×8＝320bit。The maximum total number of bits per group: 40×8=320bit.
对分组长度范围进行限制的理由是，在具体实施过程中为了简化通信系统，没有考虑OFDM系统的采样频率同步和载波频率同步，因此数据传输的长度不能太长，否则会由于误差累加造成误码。同时数据在传输过程中容易受到干扰而误码，因此使用分组传输。经过大量实际测量，分组长度为(20～80个)符号时，系统的效率最高，其他长度也可以接受，但至少要小于240个符号，否则会因为误码的影响，很难成功接收。常规通信方法中的分组长度一般比较长或无限制，可能导致最终声音不稳定。本实施方式通过对分组长度进行限制，达到了稳定可靠的传输效果。The reason for restricting the range of packet lengths is that in order to simplify the communication system in the specific implementation process, the sampling frequency synchronization and carrier frequency synchronization of the OFDM system are not considered, so the length of data transmission cannot be too long, otherwise it will cause bit errors due to error accumulation . At the same time, data is susceptible to interference and bit errors during transmission, so packet transmission is used. After a large number of actual measurements, the system has the highest efficiency when the packet length is (20-80) symbols, and other lengths are also acceptable, but at least less than 240 symbols, otherwise it will be difficult to receive successfully due to the influence of bit errors. The packet length in conventional communication methods is generally long or unlimited, which may lead to unstable final sound. In this embodiment, a stable and reliable transmission effect is achieved by limiting the packet length.
OFDM调制模块25用于对数据单元进行OFDM调制。The OFDM modulation module 25 is used to perform OFDM modulation on the data unit.
在OFDM调制模块25的调制过程中，使用了128个子载波，载波间隔Δf＝375Hz，有效子载波数为8，有效符号持续时间T＝2.67ms，信号带宽f＝3k。In the modulation process of the OFDM modulation module 25, 128 subcarriers are used, the carrier spacing Δf=375Hz, the number of effective subcarriers is 8, the effective symbol duration T=2.67ms, and the signal bandwidth f=3k.
OFDM的主要实现过程是基于傅里叶变换与逆变换。实际上，OFDM调制模块25在傅里叶逆变换操作之前还包括一预处理操作，变换之后还包括一后处理操作。具体为：The main implementation process of OFDM is based on Fourier transform and inverse transform. In fact, the OFDM modulation module 25 also includes a pre-processing operation before the inverse Fourier transform operation, and a post-processing operation after the transform. Specifically:
OFDM调制模块25对一数据单元以一个字节为单位进行串并转换，即将每个字节的8bit数据分为前后4bit，在这中间加入120个0作为冗余数据构成128个bit的一组数据，然后对这组包含128个bit的数据进行快速傅里叶逆变换，得到频域数据，待所有的分组数据都完成了频域转换后，再将各组数据还原，将并行数据转换为串行的数据流，即将得到的各分组频域数据按照原先的顺序组合为一整串的数据流，从而完成OFDM调制。上述的每个字节的8bit即为构成有效子载波的实际数据来源，在数据流传输过程中占据了T＝2.67ms的传输时间；加入的120个0，即增加了120bit的0是为了防止数据的频域混叠，在数据流传输过程中构成了Δf＝375Hz的载波间隔，可以有效的分隔数据字节。The OFDM modulation module 25 performs serial-to-parallel conversion on a data unit in units of one byte, that is, the 8-bit data of each byte is divided into 4 bits before and after, and 120 0s are added in the middle as redundant data to form a group of 128 bits Data, and then fast Fourier inverse transform is performed on this group of data containing 128 bits to obtain frequency domain data. After all grouped data have completed frequency domain conversion, each group of data is restored, and the parallel data is converted into The serial data stream, the frequency domain data of each packet to be obtained is combined into a whole series of data streams according to the original order, thereby completing OFDM modulation. The above-mentioned 8 bits of each byte are the actual data sources constituting the effective subcarriers, which occupy the transmission time of T=2.67ms during the data stream transmission process; the 120 0s added, that is, 120 bits of 0s are added to prevent The frequency domain aliasing of data constitutes a carrier interval of Δf=375Hz during data stream transmission, which can effectively separate data bytes.
循环前缀模块25用于加入循环前缀。The cyclic prefix module 25 is used to add a cyclic prefix.
在完成数据的OFDM调制后会得到128bit为单位的连续数据流，此时循环前缀模块26将每个128bit重新整合，将其中的后32bit复制添加到128bit流的前端，构成160bit的连续数据流，完成数据的循环，即实现了循环前缀的添加。After the OFDM modulation of the data is completed, a continuous data stream in units of 128 bits will be obtained. At this time, the cyclic prefix module 26 reintegrates each 128 bit, and adds the latter 32 bits to the front end of the 128 bit stream to form a continuous data stream of 160 bits. The cycle of data is completed, that is, the addition of a cyclic prefix is realized.
声音生成模块26用于生成声音信号。The sound generation module 26 is used to generate sound signals.
具体地，将经过上述处理后的数据流再调制到可以传输的频带上并生成声音信号，其处理的具体参数为：根据采样定理，采用不低于数据频率2倍的采样频率对数据流进行采样，为了较好的对数据采样，可采用不低于48kHz的采样频率，然后使用普通手机的麦克风和扬声器可接受较好的频率f＝3～7KHz作为载波频率，接着将采样得到的数据与载波信号相乘得到频带传输数据，即完成了数据的频带调制，从而得到可供声音传输的音频数据流。所生成的声音信号的频率位于下述范围：Specifically, the data stream after the above processing is modulated to a frequency band that can be transmitted to generate a sound signal. The specific parameters of the processing are: according to the sampling theorem, the data stream is processed at a sampling frequency not lower than twice the data frequency. Sampling, in order to better sample data, you can use a sampling frequency not lower than 48kHz, then use the microphone and speaker of an ordinary mobile phone to accept a better frequency f = 3 ~ 7KHz as the carrier frequency, and then compare the sampled data with The carrier signal is multiplied to obtain the frequency band transmission data, that is, the frequency band modulation of the data is completed, so as to obtain the audio data stream for sound transmission. The frequencies of the generated sound signals are in the following ranges:
(93.75*0.9*k-93.75*1.1*k)Hz，(93.75*0.9*k-93.75*1.1*k)Hz,
(86.13*0.9*k-86.13*1.1*k)Hz，(86.13*0.9*k-86.13*1.1*k)Hz,
(78.13*0.9*k-78.13*1.1*k)Hz，(78.13*0.9*k-78.13*1.1*k)Hz,
(62.5*0.9*k-62.5*1.1*k)Hz，或(62.5*0.9*k-62.5*1.1*k)Hz, or
(43.1*0.9*k-43.1*1.1*k)Hz，其中k＝0,1,...,255。(43.1*0.9*k-43.1*1.1*k)Hz, where k=0,1,...,255.
令生成的声音信号位于上述范围频率时，正好可以在两个普通录音设备的常用采样率范围取得正交性。例如，在48k采样率下，取第一组频率中任意两个都可以构成两两正交的关系。When the generated sound signal is placed in the frequency range mentioned above, the orthogonality can be obtained just in the commonly used sampling rate range of two common recording devices. For example, at a sampling rate of 48k, any two frequencies in the first group can form a pairwise orthogonal relationship.
发明人在选择信号频率范围的过程中发现，由于一般手机的喇叭可以播放的频率范围为(0～22KHz)信号，手机麦克风可以录制的频率范围为(0～22KHz)，部分手机的麦克风可以录制的频率范围为(0～9KHz)(已知的手机有小米1，努比亚手机)，在(0～3KHz)频率范围内，信号很容易受到环境噪声的影响，比如人说话的声音等。因此可以使用的频率范围为(3KHz～22KHz)。此外发明人经过测试发现，16KHz以上的信号在手机播放和接收过程中被衰减的很严重，因此不适用于传输数据，因此可以使用的频率范围为(3KHz～16KHz)。如果想要兼容所有手机，那么可以使用的频率范围为(3KHz～9KHz)。In the process of selecting the frequency range of the signal, the inventor found that since the speaker of a general mobile phone can play the signal in the frequency range of (0-22KHz), the microphone of the mobile phone can record the frequency range of (0-22KHz), and the microphone of some mobile phones can record The frequency range of the signal is (0-9KHz) (known mobile phones include Mi 1 and Nubia mobile phones). In the frequency range of (0-3KHz), the signal is easily affected by environmental noise, such as the voice of people talking. Therefore, the frequency range that can be used is (3KHz～22KHz). In addition, the inventor found through tests that the signals above 16KHz are seriously attenuated during the playback and reception of mobile phones, so they are not suitable for data transmission, so the usable frequency range is (3KHz～16KHz). If you want to be compatible with all mobile phones, the frequency range that can be used is (3KHz ~ 9KHz).
此外，经发明人研究发现，基于声音在空气中传播的衰减公式可知，衰减主要包括发射衰减和空气吸收两部分；在一般室温和相对湿度条件下，传输距离一定时，22kHz以上频率的声音传输衰减率急剧增加，因此M个载波中任意两个载波的频率差值的绝对值应小于或等于22kHz，否则在进行频谱搬移过程中会使得声波最高频率超过22kHz。考虑到一定环境噪声的存在，为维持信噪比，16kHz为较乐观的估计值；当环境噪声较大时，3kHz左右具有较强的鲁棒性。In addition, the inventors found that based on the attenuation formula of sound propagating in the air, the attenuation mainly includes two parts: emission attenuation and air absorption; The attenuation rate increases sharply, so the absolute value of the frequency difference between any two carriers among the M carriers should be less than or equal to 22kHz, otherwise the highest frequency of the sound wave will exceed 22kHz during the spectrum shifting process. Considering the existence of certain environmental noise, in order to maintain the signal-to-noise ratio, 16kHz is an optimistic estimate; when the environmental noise is large, around 3kHz has strong robustness.
发明人经过大量的实际测试得到子载波间隔Δf为(86HZ～750HZ)时,通信效果较佳。当低于86Hz时，各个子载波间容易发生频谱干扰，造成误码率提高。当高于750Hz时，频谱的利用率较低，传输码率难以提高。有效子载波数N的值可以由信号带宽f和子载波间隔Δf得到，N＝f/Δf。The inventor obtained through a large number of actual tests that when the subcarrier spacing Δf is (86HZ～750HZ), the communication effect is better. When it is lower than 86 Hz, spectrum interference is likely to occur between subcarriers, resulting in an increase in the bit error rate. When it is higher than 750Hz, the spectrum utilization rate is low, and it is difficult to increase the transmission code rate. The value of the effective subcarrier number N can be obtained from the signal bandwidth f and the subcarrier spacing Δf, N=f/Δf.
进一步地，调制模块23为了提高码率，同时使用多个载波信号传输数据。为了避免载波间相互混叠，选取相互正交的载波信号。这些相互正交的子载波满足以下公式：
其中Tsym表示信号周期。在48kHz采样频率下可以选择的正交频率有表1所示的频率。可以根据实际需求选择频率1、频率2、频率3或频率4中的几个或全部频率点。where Tsym represents the signal period. The quadrature frequencies that can be selected under the 48kHz sampling frequency are those shown in Table 1. Several or all frequency points in frequency 1, frequency 2, frequency 3 or frequency 4 can be selected according to actual needs.
又例如，在44.1kHz采样频率下可以选择的正交频率有表2所示的频率。可以根据实际需求选择频率1、频率2、频率3或频率4中的几个或者全部频率点。For another example, the quadrature frequencies that can be selected at a sampling frequency of 44.1kHz are those shown in Table 2. Several or all frequency points in frequency 1, frequency 2, frequency 3 or frequency 4 can be selected according to actual needs.
本实施方式设计的声波通信发送装置实现了对数据的快速、准确、高效的调制和发送，在采用BPSK调制的系统中最高可实现2.4kbps的传输速率，而在采用QPSK调制的系统中最高的传输速率可达到4.8kbps。The acoustic wave communication sending device designed in this embodiment realizes the fast, accurate and efficient modulation and transmission of data, and the highest transmission rate of 2.4kbps can be realized in the system adopting BPSK modulation, and the highest transmission rate in the system adopting QPSK modulation The transfer rate can reach 4.8kbps.
需要说明的是，在本文中，诸如第一和第二等之类的关系术语仅仅用来将一个实体或者操作与另一个实体或操作区分开来，而不一定要求或者暗示这些实体或操作之间存在任何这种实际的关系或者顺序。而且，术语“包括”、“包含”或者其任何其他变体意在涵盖非排他性的包含，从而使得包括一系列要素的过程、方法、物品或者终端设备不仅包括那些要素，而且还包括没有明确列出的其他要素，或者是还包括为这种过程、方法、物品或者终端设备所固有的要素。在没有更多限制的情况下，由语句“包括……”或“包含……”限定的要素，并不排除在包括所述要素的过程、方法、物品或者终端设备中还存在另外的要素。此外，在本文中，“大于”、“小于”、“超过”等理解为不包括本数；“以上”、“以下”、“以内”等理解为包括本数。It should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is a relationship between these entities or operations. There is no such actual relationship or order between them. Furthermore, the term "comprises", "comprises" or any other variation thereof is intended to cover a non-exclusive inclusion such that a process, method, article, or terminal equipment comprising a set of elements includes not only those elements, but also includes elements not expressly listed. other elements identified, or also include elements inherent in such a process, method, article, or end-equipment. Without further limitations, an element defined by the words "comprising..." or "comprising..." does not exclude the presence of additional elements in the process, method, article or terminal device comprising said element. In addition, in this article, "greater than", "less than", "exceeding" and so on are understood as not including the original number; "above", "below", "within" and so on are understood as including the original number.
本领域内的技术人员应明白，上述各实施例可提供为方法、装置、或计算机程序产品。这些实施例可采用完全硬件实施例、完全软件实施例、或结合软件和硬件方面的实施例的形式。上述各实施例涉及的方法中的全部或部分步骤可以通过程序来指令相关的硬件来完成，所述的程序可以存储于计算机设备可读取的存储介质中，用于执行上述各实施例方法所述的全部或部分步骤。所述计算机设备，包括但不限于：个人计算机、服务器、通用计算机、专用计算机、网络设备、嵌入式设备、可编程设备、智能移动终端、智能家居设备、穿戴式智能设备、车载智能设备等；所述的存储介质，包括但不限于：RAM、ROM、磁碟、磁带、光盘、闪存、U盘、移动硬盘、存储卡、记忆棒、网络服务器存储、网络云存储等。Those skilled in the art should understand that the above-mentioned embodiments may be provided as methods, devices, or computer program products. These embodiments can take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. All or part of the steps in the methods involved in the above-mentioned embodiments can be completed by instructing related hardware through a program, and the program can be stored in a storage medium readable by a computer device, and is used to execute the methods described in the above-mentioned embodiments. all or part of the steps described above. The computer equipment includes, but is not limited to: personal computers, servers, general-purpose computers, special-purpose computers, network equipment, embedded equipment, programmable equipment, intelligent mobile terminals, intelligent home equipment, wearable intelligent equipment, vehicle-mounted intelligent equipment, etc.; The storage medium includes, but is not limited to: RAM, ROM, magnetic disk, tape, optical disk, flash memory, U disk, mobile hard disk, memory card, memory stick, network server storage, network cloud storage, etc.
上述各实施例是参照根据实施例所述的方法、设备(系统)、和计算机程序产品的流程图和/或方框图来描述的。应理解可由计算机程序指令实现流程图和/或方框图中的每一流程和/或方框、以及流程图和/或方框图中的流程和/或方框的结合。可提供这些计算机程序指令到计算机设备的处理器以产生一个机器，使得通过计算机设备的处理器执行的指令产生用于实现在流程图一个流程或多个流程和/或方框图一个方框或多个方框中指定的功能的装置。The above-mentioned embodiments are described with reference to the flowcharts and/or block diagrams of the methods, devices (systems), and computer program products according to the embodiments. It should be understood that each procedure and/or block in the flowchart and/or block diagram, and a combination of procedures and/or blocks in the flowchart and/or block diagram can be realized by computer program instructions. These computer program instructions can be provided to the processor of the computer device to produce a machine, so that the instructions executed by the processor of the computer device can be used to implement one or more procedures in the flowchart and/or one or more blocks in the block diagram. means of the function specified in the box.
这些计算机程序指令也可存储在能引导计算机设备以特定方式工作的计算机设备可读存储器中，使得存储在该计算机设备可读存储器中的指令产生包括指令装置的制造品，该指令装置实现在流程图一个流程或多个流程和/或方框图一个方框或多个方框中指定的功能。These computer program instructions may also be stored in a computer device readable memory capable of directing a computer device to operate in a specific manner, such that the instructions stored in the computer device readable memory produce an article of manufacture comprising instruction means implemented in a process Diagram of a process or processes and/or a block diagram with a function specified in a box or boxes.
这些计算机程序指令也可装载到计算机设备上，使得在计算机设备上执行一系列操作步骤以产生计算机实现的处理，从而在计算机设备上执行的指令提供用于实现在流程图一个流程或多个流程和/或方框图一个方框或多个方框中指定的功能的步骤。These computer program instructions can also be loaded on a computer device, so that a series of operational steps are executed on the computer device to produce a computer-implemented process, so that the instructions executed on the computer device are used to implement one or more processes in the flowchart and/or steps of the function specified in one or more blocks of the block diagram.
尽管已经对上述各实施例进行了描述，但本领域内的技术人员一旦得知了基本创造性概念，则可对这些实施例做出另外的变更和修改，所以以上所述仅为本发明的实施例，并非因此限制本发明的专利保护范围，凡是利用本发明说明书及附图内容所作的等效结构或等效流程变换，或直接或间接运用在其他相关的技术领域，均同理包括在本发明的专利保护范围之内。Although the above-mentioned embodiments have been described, those skilled in the art can make additional changes and modifications to these embodiments once they know the basic creative concept, so the above-mentioned are only the implementation of the present invention For example, it is not intended to limit the scope of patent protection of the present invention. Any equivalent structure or equivalent process transformation made by using the description and drawings of the present invention, or directly or indirectly used in other related technical fields, is also included in this patent. Inventions within the scope of patent protection.
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410385343.4ACN105450312B (en) | 2014-08-07 | 2014-08-07 | Acoustic wave communication sending method and device |
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410385343.4ACN105450312B (en) | 2014-08-07 | 2014-08-07 | Acoustic wave communication sending method and device |
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| CN105450312Atrue CN105450312A (en) | 2016-03-30 |
| CN105450312B CN105450312B (en) | 2018-12-28 |
| Application Number | Title | Priority Date | Filing Date |
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| CN201410385343.4AActiveCN105450312B (en) | 2014-08-07 | 2014-08-07 | Acoustic wave communication sending method and device |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106161785A (en)* | 2016-06-28 | 2016-11-23 | 武汉大学 | A kind of smart mobile phone real-time communication method based on hidden acoustical signal |
| CN107437967A (en)* | 2017-06-08 | 2017-12-05 | 深圳市迈岭信息技术有限公司 | Data transmission method based on sound wave, send equipment and receiving device |
| CN111313979A (en)* | 2020-01-21 | 2020-06-19 | 北京达佳互联信息技术有限公司 | Data transmission method and device, electronic equipment and storage medium |
| CN111758228A (en)* | 2017-12-19 | 2020-10-09 | 灵思耳有限公司 | Phase shift keying signaling tones |
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101394200A (en)* | 2008-11-11 | 2009-03-25 | 国网电力科学研究院 | A power line carrier data transmission method with zero frequency conversion and adaptive frequency selection |
| US20110134971A1 (en)* | 2008-08-14 | 2011-06-09 | Sk Telecom Co., Ltd. | System and method for data reception and transmission in audible frequency band |
| CN102449500A (en)* | 2010-02-18 | 2012-05-09 | 松下电器产业株式会社 | Ultrasonic measurement method and ultrasonic measurement device |
| CN102546032A (en)* | 2012-01-20 | 2012-07-04 | 北京印天网真科技有限公司 | Wireless transmitting and receiving method, wireless transmitting and receiving device, wireless communication method and wireless communication system |
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20110134971A1 (en)* | 2008-08-14 | 2011-06-09 | Sk Telecom Co., Ltd. | System and method for data reception and transmission in audible frequency band |
| CN101394200A (en)* | 2008-11-11 | 2009-03-25 | 国网电力科学研究院 | A power line carrier data transmission method with zero frequency conversion and adaptive frequency selection |
| CN102449500A (en)* | 2010-02-18 | 2012-05-09 | 松下电器产业株式会社 | Ultrasonic measurement method and ultrasonic measurement device |
| CN102546032A (en)* | 2012-01-20 | 2012-07-04 | 北京印天网真科技有限公司 | Wireless transmitting and receiving method, wireless transmitting and receiving device, wireless communication method and wireless communication system |
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106161785A (en)* | 2016-06-28 | 2016-11-23 | 武汉大学 | A kind of smart mobile phone real-time communication method based on hidden acoustical signal |
| CN106161785B (en)* | 2016-06-28 | 2019-06-11 | 武汉大学 | A real-time communication method of smart phone based on concealed sound signal |
| CN107437967A (en)* | 2017-06-08 | 2017-12-05 | 深圳市迈岭信息技术有限公司 | Data transmission method based on sound wave, send equipment and receiving device |
| CN111758228A (en)* | 2017-12-19 | 2020-10-09 | 灵思耳有限公司 | Phase shift keying signaling tones |
| CN111313979A (en)* | 2020-01-21 | 2020-06-19 | 北京达佳互联信息技术有限公司 | Data transmission method and device, electronic equipment and storage medium |
| CN111313979B (en)* | 2020-01-21 | 2021-09-17 | 北京达佳互联信息技术有限公司 | Data transmission method and device, electronic equipment and storage medium |
| Publication number | Publication date |
|---|---|
| CN105450312B (en) | 2018-12-28 |
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