一种 CMMB系统的终端测试信号生成方法和装置 技术领域 Method and device for generating terminal test signal of CMMB system
本发明涉及通信及广播电视领域， 尤其是涉及一种数字多媒体广播系 统的测试信号的生成方法和装置。 背景技术 The present invention relates to the field of communication and broadcast television, and more particularly to a method and apparatus for generating test signals for a digital multimedia broadcast system. Background technique
数字多媒体广播除了覆盖面广、 节目容量大之外， 最大的特点就是具 有广播性， 一点对多点， 一点对面， 广播的质量和成本与用户的数量无关。 因此， 数字多媒体广播在国家信息基础设施建设和国家信息安全战略中具 有重要地位。 In addition to wide coverage and large program capacity, digital multimedia broadcasting has the most distinctive feature: broadcastability, point-to-multipoint, and point-to-point. The quality and cost of broadcasting are independent of the number of users. Therefore, digital multimedia broadcasting plays an important role in national information infrastructure construction and national information security strategies.
CMMB ( China Mobile Multimedia Broadcasting, 中国移动多媒体广播 ) 是我国研发的具有自主知识产权的数字多媒体广播标准。 CMMB系统通过卫 星和地面基站， 可以实现天地一体的大面积广播覆盖。 用户可以通过终端， 移 动接收多路音、 视频广播节目。 CMMB (China Mobile Multimedia Broadcasting) is a digital multimedia broadcasting standard developed by China with independent intellectual property rights. The CMMB system can realize large-area broadcast coverage of heaven and earth through satellites and ground base stations. Users can receive multi-channel and video broadcast programs through the terminal.
终端设备生产商为了进行对终端的测试， 需要各种标准的测试信号。通常 的方法是使用实际的发射机生成测试信号。但发射设备的价格较昂贵，且除了 能生成系统规定格式的信号之夕卜，不能生成其它类型的信号，设备使用率较低。 此外， 若需要生成某种信道环境下的测试信号，通常还要将发射机生成的信号 通过信道模拟器。 信道模拟设备的价格同样较昂贵。 因此， 需要一种通用、 灵 活的测试信号生成方法和装置。 发明内容 In order to test the terminal, the terminal equipment manufacturer needs various standard test signals. The usual method is to generate a test signal using the actual transmitter. However, the cost of the transmitting device is relatively high, and in addition to generating a signal in a system-specified format, other types of signals cannot be generated, and the device usage rate is low. In addition, if it is necessary to generate a test signal in a certain channel environment, the signal generated by the transmitter is usually passed through the channel simulator. Channel analog devices are also more expensive. Therefore, there is a need for a versatile and flexible test signal generation method and apparatus. Summary of the invention
为克服现有技术中存在的上述缺陷， 本发明的目的是提供一种 CMMB 系统的终端测试信号生成方法和装置， 本发明利用信号处理平台和信号发 生器生成测试信号， 相比较于利用发射机生成测试信号， 具有灵活通用的 特点， 并且可以节约成本。 In order to overcome the above-mentioned drawbacks existing in the prior art, an object of the present invention is to provide a method and apparatus for generating a terminal test signal of a CMMB system, which uses a signal processing platform and a signal generator to generate a test signal, compared to using a transmitter Generate test signals, which are flexible and versatile, and can save costs.
本发明的一个目的是提供一种 CMMB系统的终端测试信号生成装置， 该装置包括， 信号处理平台， 用于对输入的信息进行编码和调制， 生成符合系统物 理层帧结构的信号；It is an object of the present invention to provide a terminal test signal generating apparatus for a CMMB system, the apparatus comprising a signal processing platform, configured to encode and modulate the input information to generate a signal conforming to a frame structure of a physical layer of the system;
信号截取转换装置， 用于对信号进行截取和转换， 其输入信号为上述 信号处理平台输出的符合系统物理层帧结构的信号； a signal intercepting and converting device, configured to intercept and convert the signal, wherein the input signal is a signal output by the signal processing platform conforming to a frame structure of a physical layer of the system;
信号发生器， 用于将信号以指定的频率和幅度循环发送， 其输入信号 为上述信号截取转换装置输出的符合信号发生器输入格式的信号。 The signal generator is configured to cyclically transmit the signal at a specified frequency and amplitude, and the input signal is a signal output by the conversion device that conforms to the input format of the signal generator.
本发明的另一个目的是提供一种 CMMB 系统的终端测试信号生成方 法， 该方法包括， Another object of the present invention is to provide a terminal test signal generating method for a CMMB system, the method comprising
首先对输入的信息进行编码调制，生成符合系统物理层帧结构的信号。 然后将上述符合系统物理层帧结构的信号进行截取和转换。 最后将上述截 取转换后的信号以指定的频率和幅度循环发送， 并作为测试信号发送到终 端。 First, the input information is coded and modulated to generate a signal conforming to the frame structure of the physical layer of the system. The above-mentioned signals conforming to the frame structure of the physical layer of the system are then intercepted and converted. Finally, the above-mentioned intercepted converted signal is cyclically transmitted at a specified frequency and amplitude, and sent as a test signal to the terminal.
其中， 上述方法中对输入的信息进行编码调制， 进一步包括如下步骤： 首先将输入的信息按照低位比特优先的原则划分为字节，进行 RS编码 和字节交织，再将上述 RS编码和字节交织后的字节按照低位比特优先的原 则拆分为比特流， 进行 LDPC编码和比特交织， 而后进行星座映射。 将星 座映射后的符号与离散导频和连续导频复接在一起，组成 OFDM频域符号， 进行 OFDM调制 ,并对每个 OFDM符号前加入循环前缀，经过加窗交叠后 , 组成一个时隙， 每 40个时隙复接成一个物理层帧信号。 最后对复接成帧后 的信号进行滤波。 The method for encoding and modulating the input information further includes the following steps: First, the input information is divided into bytes according to the principle of low-order bit priority, RS coding and byte interleaving are performed, and the RS code and the byte are further performed. The interleaved bytes are split into bit streams according to the principle of low bit priority, LDPC coding and bit interleaving are performed, and then constellation mapping is performed. The constellation-mapped symbols are multiplexed with the scattered pilot and the continuous pilot to form an OFDM frequency domain symbol, and OFDM modulation is performed, and a cyclic prefix is added to each OFDM symbol, and after being overlapped by windowing, a time is formed. Gap, every 40 time slots are multiplexed into one physical layer frame signal. Finally, the signal after multiplexing is framed.
本发明提出的一种 CMMB系统的终端测试信号生成方法和装置， 具有以 下的特点： The method and device for generating a terminal test signal of a CMMB system proposed by the present invention have the following features:
( 1 )信号发生器是可以在多种场合下广泛使用的通用设备， 因此本 发明相比较于传统的使用实际的发射机生成测试信号的方法设备， 灵活性高、 设备利用率高， 并且节约成本。 (1) The signal generator is a general-purpose device that can be widely used in various occasions, and therefore the present invention has higher flexibility, high equipment utilization, and economy compared to the conventional method of generating a test signal using an actual transmitter. cost.
( 2 )测试信号完全满足系统的物理层帧结构， 可以直接用于终端接 收。 (2) The test signal fully satisfies the physical layer frame structure of the system and can be directly used for terminal reception.
( 3 )测试信号可以承载不同类型的信息， 用于对终端进行各种类型 的测试， 包括接收门限测试、 音频播放质量测试、 视频播放质量测试以及 误码率测试等。(3) The test signal can carry different types of information, and is used for performing various types of tests on the terminal, including receiving threshold testing, audio playback quality testing, video playback quality testing, and the like. Bit error rate test, etc.
( 4 )测试信号可以配置成不同的编码和调制模式， 用于对终端进行 各种模式下的测试， 包括信道带宽模式、 交织模式、 RS编码模式、 LDPC编 码模式、 星座映射模式、 扰码模式等。 (4) The test signal can be configured into different coding and modulation modes for testing the terminal in various modes, including channel bandwidth mode, interleaving mode, RS coding mode, LDPC coding mode, constellation mapping mode, and scrambling mode. Wait.
( 5 )测试信号可以模拟通过各种类型信道， 用于对终端进行各种信 道环境下的测试， 包括 AWGN信道、 多径衰落信道、 时变信道等。 (5) The test signal can be simulated through various types of channels for testing the terminal in various channel environments, including AWGN channels, multipath fading channels, time varying channels, and the like.
本发明的上述其他目的及其特征进一步适用的范围， 可由下列的详细 说明中清楚得知。 但是， 这些详细的说明和所提到的实施例仅供说明作用， 并非构成对本发明的限制， 本领域中的技术人员应该可以理解其它变化形 式。 附图说明 Further scope of the above-described other objects and features of the present invention will be apparent from the following detailed description. However, the detailed description and the examples are merely illustrative and are not intended to limit the invention, and other variations will be apparent to those skilled in the art. DRAWINGS
图 1为根据本发明的 CMMB系统的终端测试信号生成装置的结构示意 图； 1 is a schematic structural view of a terminal test signal generating apparatus of a CMMB system according to the present invention;
图 2为根据本发明的 CMMB系统的终端测试信号生成方法的流程图； 图 3为根据本发明的一个优选实施例的生成测试终端视频播放质量的 测试信号的流程图； 以及 2 is a flow chart of a method for generating a terminal test signal of a CMMB system according to the present invention; FIG. 3 is a flow chart showing a test signal for generating a video playback quality of a test terminal according to a preferred embodiment of the present invention;
图 4为根据本发明的另一个优选实施例的生成测试终端误码率性能的 测试信号的流程图。 具体实施方式 4 is a flow diagram of a test signal for generating a bit error rate performance of a test terminal in accordance with another preferred embodiment of the present invention. detailed description
下面详细描述本发明的实施例， 所述实施例的示例在附图中示出， 其 中自始至终相同或类似的标号表示相同或类似的元件或具有相同或类似功 能的元件。 下面通过参考附图描述的实施例是示例性的， 仅用于解释本发 明， 而不能解释为对本发明的限制。 The embodiments of the present invention are described in detail below, and the examples of the embodiments are illustrated in the drawings, wherein the same or similar reference numerals are used to refer to the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the drawings are intended to be illustrative only and not to be construed as limiting.
[实施方式 1] [Embodiment 1]
本发明的一个目的是提供一种 CMMB 系统的终端测试信号生成装置 100 , 如图 1所示， 该测试信号生成装置 100包括信号处理平台 101、 信号 截取转换装置 102和信号发生器 103。 其中， 信号处理平台 101对输入的信息进行编码和调制， 产生符合系 统物理层帧结构的信号。 在本实施例中， 信号处理平台 101 可以是软件平 台或硬件平台， 其中， 软件平台可以是基于 C语言、 MATLAB等的软件平 台； 硬件平台可以是基于 DSP、 FPGA等的硬件平台。An object of the present invention is to provide a terminal test signal generating apparatus 100 of a CMMB system. As shown in FIG. 1, the test signal generating apparatus 100 includes a signal processing platform 101, a signal intercepting converting apparatus 102, and a signal generator 103. The signal processing platform 101 encodes and modulates the input information to generate a signal conforming to the frame structure of the physical layer of the system. In this embodiment, the signal processing platform 101 may be a software platform or a hardware platform, where the software platform may be a software platform based on C language, MATLAB, etc.; the hardware platform may be a hardware platform based on DSP, FPGA, or the like.
此外， 信号处理平台 101在处理信号过程中， 可以将信号配置成不同 的编码和调制模式， 包括信道带宽模式、 交织模式、 RS 编码模式、 LDPC 编码模式、 星座映射模式、 扰码模式等， 可以对终端进行不同模式下的测 试。 In addition, the signal processing platform 101 may configure the signal into different coding and modulation modes during the processing of the signal, including a channel bandwidth mode, an interleaving mode, an RS coding mode, an LDPC coding mode, a constellation mapping mode, a scrambling mode, and the like. Test the terminal in different modes.
另外， 信号处理平台 101 可以模拟信号通过不同类型的信道， 包括 AWGN信道、 多径衰落信道、 时变信道等， 用于生成在该类信道环境下的测 试信号。 In addition, the signal processing platform 101 can simulate signals through different types of channels, including AWGN channels, multipath fading channels, time varying channels, etc., for generating test signals in such channel environments.
信号截取转换装置 102对信号处理平台 101输出的符合系统物理层帧 结构的信号进行截取， 并转换成满足信号发生器 103输入格式的信号。 The signal interception conversion means 102 intercepts the signal output from the signal processing platform 101 in accordance with the frame structure of the system physical layer, and converts it into a signal satisfying the input format of the signal generator 103.
其中， 信号截取转换装置 102所截取信号的总点数必须小于信号发生 器 103 内部存储容量的限制。 并且， 信号可以以帧或者时隙为单位进行截 取。 当以时隙为单位进行截取时， 所截取的时隙数可以整除一帧中的时隙 数， 以便终端能够正确的实现同步。 The total number of points of the signal intercepted by the signal interception conversion device 102 must be less than the limit of the internal storage capacity of the signal generator 103. Also, the signal can be intercepted in units of frames or time slots. When intercepting in units of time slots, the number of time slots intercepted can be divided by the number of time slots in one frame, so that the terminal can correctly implement synchronization.
信号发生器 103将信号截取转换装置 102输出的符合信号发生器 103 格式的信号以指定的频率和幅度循环发送， 即， 发送测试信号到终端。 The signal generator 103 cyclically transmits a signal in accordance with the signal generator 103 format output from the signal intercepting conversion means 102 at a specified frequency and amplitude, i.e., transmits a test signal to the terminal.
本发明的另一个目的是提供一种 CMMB 系统的终端测试信号生成方 法， 该方法是利用信号处理平台和信号发生器生成用于终端性能测试的标 准测试信号， 如图 2所示， 包括以下步骤： Another object of the present invention is to provide a terminal test signal generating method for a CMMB system, which uses a signal processing platform and a signal generator to generate a standard test signal for terminal performance testing, as shown in FIG. 2, including the following steps. :
S201 : 对输入的信息进行编码调制， 生成符合系统物理层帧结构的信 号； S201: code and modulate the input information to generate a signal conforming to a frame structure of a physical layer of the system;
S202: 然后将上述符合系统物理层帧结构的信号进行截取和转换； S203 : 将截取转换后的信号以指定的频率和幅度循环发送， 并作为测 试信号发送到终端。 S202: The above-mentioned signal conforming to the frame structure of the physical layer of the system is intercepted and converted. S203: The intercepted converted signal is cyclically transmitted at a specified frequency and amplitude, and sent to the terminal as a test signal.
本发明涉及的 CMMB 系统的终端测试信号生成方法及装置中输入的信 息主要包括系统控制信息、 电子业务指南、 视频流、 音频流和数据流等。 根据信息类型的不同， 可以对终端进行不同类型的测试， 包括接收门限测 试、 音频播放质量测试、 视频播放质量测试以及误码率测试等。The terminal test signal generation method and device of the CMMB system according to the present invention mainly include system control information, an electronic service guide, a video stream, an audio stream, and a data stream. Depending on the type of information, different types of tests can be performed on the terminal, including reception threshold testing, audio playback quality testing, video playback quality testing, and bit error rate testing.
下面结合图 1和图 2 , 分别以生成终端的视频播放质量的测试信号和误 码率性能的测试信号为例 ,对本发明涉及的利用信号处理平台和信号发生器生 成测试信号的方法进行详细说明。 The following takes the test signal of the video playback quality of the terminal and the test signal of the bit error rate performance as an example to describe the method for generating the test signal by using the signal processing platform and the signal generator according to the example of FIG. 1 and FIG. 2 respectively. .
[实施方式 2] [Embodiment 2]
在本实施例中， 本发明的目的是生成用于测试 CMMB 终端的视频播放 质量的测试信号。 In the present embodiment, an object of the present invention is to generate a test signal for testing the quality of video playback of a CMMB terminal.
在本实施例中， 输入的信息为系统控制信息、 电子业务指南和视频流。 其中， 系统控制信息为终端提供系统的相关信息， 如中心频率、 业务所占 时隙、 编码和调制模式等； 电子业务指南为终端提供广播业务的相关信息， 如业务名称、 播放时间、 内容梗概等； 视频流为终端提供视频业务。 In this embodiment, the input information is system control information, an electronic service guide, and a video stream. The system control information provides the terminal with relevant information of the system, such as a center frequency, a time slot occupied by the service, a coding and a modulation mode, and the like; the electronic service guide provides the terminal with information about the broadcast service, such as a service name, a play time, and a content outline. Etc; The video stream provides video services for the terminal.
结合图 3所示，信号处理平台 101釆用 Cadence公司的 SPW软件搭建， 用于对输入的信息进行编码和调制， 产生符合 CMMB 物理层帧结构的信 号， 具体步骤如下： As shown in FIG. 3, the signal processing platform 101 is constructed using Cadence's SPW software for encoding and modulating the input information to generate a signal conforming to the CMMB physical layer frame structure. The specific steps are as follows:
S301 : RS编码和字节交织， 将输入的信息按照低位比特优先 （LSB ) 的 原则划分为字节， 进行 RS编码和字节交织。 S301: RS coding and byte interleaving, and the input information is divided into bytes according to the principle of low bit priority (LSB), and RS coding and byte interleaving are performed.
其中， 系统控制信息釆用 RS ( 240, 240 )编码， 字节交织模式 1 ; Wherein, the system control information is encoded by RS (240, 240), byte interleaving mode 1;
电子业务指南釆用 RS ( 240, 224 )编码， 字节交织模式 1 ; The electronic service guide uses RS (240, 224) encoding, byte interleaving mode 1;
视频流釆用 RS ( 240, 224 )编码， 字节交织模式 2。 The video stream is encoded by RS (240, 224), byte interleaving mode 2.
S302: LDPC编码和比特交织， 将 RS编码和字节交织后的字节按照低位 比特优先（LSB )的原则拆分为比特流， 进行 LDPC编码和比特交织。 所有信 号均釆用 1/2码率 LDPC编码。 S302: LDPC coding and bit interleaving, and dividing the RS coded and byte-interleaved bytes into a bit stream according to the principle of low bit priority (LSB), performing LDPC coding and bit interleaving. All signals are encoded with 1/2 code rate LDPC.
S303: 星座映射， 将比特交织后的比特流进行星座映射。 S303: Constellation mapping, performing constellation mapping on the bit-interleaved bit stream.
其中， 系统控制信息釆用 BPSK映射； Wherein, the system control information is BPSK mapped;
电子业务指南釆用 QPSK映射； The electronic service guide uses QPSK mapping;
视频流釆用 16QAM映射。 Video streaming uses 16QAM mapping.
S304: OFDM调制， 将星座映射后的符号与离散导频和连续导频复接在 一起， 组成 OFDM频域符号。 每个 OFDM符号包括 3076个有效子载波。 有 效子载波上的所有符号均被一个复伪随机（PN )序列扰码。 PN序列的初始值 釆用选项 0。 将扰码后有效子载波通过 4096点的逆快速傅里叶变换（IFFT ) 变换为 OFDM符号。S304: OFDM modulation, multiplexing the constellation mapped symbols with the scattered pilots and the continuous pilots to form an OFDM frequency domain symbol. Each OFDM symbol includes 3076 active subcarriers. Have All symbols on the effect carrier are scrambled by a complex pseudo-random (PN) sequence. The initial value of the PN sequence uses option 0. The scrambled effective subcarrier is transformed into an OFDM symbol by an inverse fast Fourier transform (IFFT) of 4096 points.
S305: 复接成帧， 在每个 OFDM符号前加入循环前缀（CP )。 每 53 个 OFDM符号、 2个同步信号和 1个发射机标识经过加窗交叠后组成一个时隙， 每 40个时隙复接成一个物理层信号帧。 S305: multiplex framing, adding a cyclic prefix (CP) before each OFDM symbol. Each 53 OFDM symbols, 2 sync signals, and 1 transmitter identifier are windowed to form a time slot, and each 40 time slots are multiplexed into one physical layer signal frame.
其中， 系统控制信息占用时隙 0; Wherein, the system control information occupies a time slot 0;
电子业务指南占用时隙 1和 2; The electronic service guide occupies slots 1 and 2;
视频流占用时隙 3和 4; The video stream occupies slots 3 and 4;
剩余的时隙可以任意填充。 The remaining time slots can be arbitrarily filled.
S306: 滤波， 滤波器对复接成帧后的信号进行滤波； S306: Filtering, filtering the signal after multiplexing the framing;
S307: 对滤波后的信号以时隙为单位进行截取， 截取时隙 0-4。 在对信号 进行截取时 , 截取信号的总点数小于信号发生器内部存储容量。 S307: The filtered signal is intercepted in units of time slots, and the time slot 0-4 is intercepted. When the signal is intercepted, the total number of points of the intercepted signal is less than the internal storage capacity of the signal generator.
S308: 将上述截取后的信号转换成满足矢量信号发生器（ VSG ) 4438C输 入格式的信号。 S308: Convert the above intercepted signal into a signal that satisfies the vector signal generator (VSG) 4438C input format.
S309: 矢量信号发生器（ VSG ) 4438C将输入的信号以 666MHz的频率和 OdB的幅度进行循环发送。 S309: Vector Signal Generator (VSG) The 4438C cyclically transmits the input signal at a frequency of 666 MHz and an amplitude of OdB.
上述测试信号通过天线发射出来。这样， 终端可以接收到一路以 1秒为周 期循环播放的视频节目， 可以进行视频播放质量测试。 The above test signal is transmitted through the antenna. In this way, the terminal can receive a video program that is cyclically played in a cycle of 1 second, and can perform video playback quality testing.
如上所述， 首先， 信号处理平台对输入的系统控制信息、 电子业务指南和 视频流进行编码和调制处理。 然后，信号截取转换装置对信号处理平台的输出 信号以时隙为单位进行截取， 并转换成满足矢量信号发生器输入格式的信号。 最后， 矢量信号发生器将将输入信号以指定的频率和幅度循环发送， 并通过天 线发射出来。 由此， 终端接收承载有系统控制信息、 电子业务指南和视频流三 种信息的标准测试信号， 对视频播放质量进行测试。 As described above, first, the signal processing platform encodes and modulates the input system control information, electronic service guide, and video stream. Then, the signal interception conversion means intercepts the output signal of the signal processing platform in units of time slots, and converts it into a signal satisfying the input format of the vector signal generator. Finally, the vector signal generator will cycle the input signal at the specified frequency and amplitude and transmit it through the antenna. Thus, the terminal receives a standard test signal carrying three types of information: system control information, electronic service guide, and video stream, and tests video playback quality.
[实施方式 3] [Embodiment 3]
在本实施例中， 本发明的目的是生成用于测试 CMMB终端的误码率性 能的测试信号。 In the present embodiment, an object of the present invention is to generate a test signal for testing the bit error rate performance of a CMMB terminal.
在本实施例中， 输入的信息为系统控制信息和数据流。 其中， 系统控 制信息为终端提供系统的相关信息， 如中心频率、 业务所占时隙、 编码和 调制模式等； 数据流为终端提供数据业务， 其中， 数据流具有固定格式。In this embodiment, the input information is system control information and a data stream. Among them, system control The information provides the terminal with information about the system, such as the center frequency, the time slot occupied by the service, the coding and modulation mode, etc.; the data stream provides the data service for the terminal, wherein the data stream has a fixed format.
结合图 4所示， 信号处理平台釆用 Synopsys公司的 CCSS软件搭建， 用于对输入的信息进行编码和调制， 产生符合 CMMB 物理层帧结构的信 号， 具体步骤如下： As shown in Figure 4, the signal processing platform is built using Synopsys CCSS software to encode and modulate the input information to produce a signal that conforms to the CMMB physical layer frame structure. The specific steps are as follows:
S401 : RS编码和字节交织， 将输入的信息按照低位比特优先 （LSB ) 的 原则划分为字节， 进行 RS编码和字节交织。 S401: RS coding and byte interleaving, and the input information is divided into bytes according to the principle of low bit priority (LSB), and RS coding and byte interleaving are performed.
其中， 系统控制信息釆用 RS ( 240, 240 )编码， 字节交织模式 1 ; Wherein, the system control information is encoded by RS (240, 240), byte interleaving mode 1;
数据流釆用 RS ( 240,176 )编码， 字节交织模式 1。 The data stream is encoded in RS (240, 176), byte interleaved mode 1.
S402: LDPC编码和比特交织， 将 RS编码和字节交织后的字节按照低位 比特优先 （LSB ) 的原则拆分为比特流， 进行 LDPC编码和比特交织。 S402: LDPC coding and bit interleaving, and dividing the RS coded and byte-interleaved bytes into a bit stream according to the principle of low bit priority (LSB), performing LDPC coding and bit interleaving.
其中， 系统控制信息釆用 1/2码率 LDPC编码； Wherein, the system control information is encoded by 1/2 code rate LDPC;
数据流釆用 3/4码率 LDPC编码。 The data stream is LDPC coded at 3/4 rate.
S403: 星座映射， 将比特交织后的比特流进行星座映射。 S403: Constellation mapping, performing constellation mapping on the bit-interleaved bit stream.
其中， 系统控制信息釆用 BPSK映射； Wherein, the system control information is BPSK mapped;
数据流釆用 QPSK映射。 The data stream is mapped using QPSK.
S404: OFDM调制， 将星座映射后的符号与离散导频和连续导频复接在 一起， 组成 OFDM频域符号。 每个 OFDM符号包括 3076个有效子载波。 有 效子载波上的所有符号均被一个复伪随机（PN )序列扰码。 PN序列的初始值 釆用选项 0。 S404: OFDM modulation, multiplexing the constellation mapped symbols with the scattered pilot and the continuous pilot to form an OFDM frequency domain symbol. Each OFDM symbol includes 3076 active subcarriers. All symbols on the effective subcarrier are scrambled by a complex pseudorandom (PN) sequence. The initial value of the PN sequence uses option 0.
将扰码后有效子载波通过 4096 点的逆快速傅里叶变换（IFFT ) 变换为 OFDM符号。 The scrambled effective subcarriers are transformed into OFDM symbols by an inverse fast Fourier transform (IFFT) of 4096 points.
S405: 复接成帧， 在每个 OFDM符号前加入循环前缀（CP )。 每 53 个 OFDM符号、 2个同步信号和 1个发射机标识经过加窗交叠后组成一个时隙， 每 40个时隙复接成一个物理层信号帧。 S405: multiplex framing, adding a cyclic prefix (CP) before each OFDM symbol. Each 53 OFDM symbols, 2 sync signals, and 1 transmitter identifier are windowed to form a time slot, and each 40 time slots are multiplexed into one physical layer signal frame.
其中， 系统控制信息占用时隙 0; Wherein, the system control information occupies a time slot 0;
数据流占用时隙 1-3; The data stream occupies slots 1-3;
剩余的时隙可以任意填充。 The remaining time slots can be arbitrarily filled.
S406: 上釆样和滤波， 滤波器对复接成帧后的信号进行 4倍上釆样， 并对 信号进行滤波，S406: uploading and filtering, the filter performs 4 times uploading on the multiplexed signal, and Signal filtering,
实施上釆样处理的信号，相对于未实施上釆样处理的信号， 其信号质量更 好。 The signal that is subjected to the sample processing is better in signal quality than the signal that is not subjected to the sample processing.
S407: 模拟加性高斯白噪声 （AWGN )信道， 在滤波后的信号上叠加指定 功率的高斯白噪声， 模拟信号通过 AWGN信道， S407: Simulating an additive white Gaussian white noise (AWGN) channel, superimposing a Gaussian white noise of a specified power on the filtered signal, and the analog signal passes through the AWGN channel.
在本实施例的步骤 407中， 滤波后的信号亦可以模拟通过其他类型信道， 包括多径衰落信道， 例如 Rayleigh信道、 Ricean信道， 时变信道， 例如 Jakes 模型等。 In step 407 of the embodiment, the filtered signal can also be simulated through other types of channels, including multipath fading channels, such as Rayleigh channels, Ricean channels, time varying channels, such as the Jakes model.
S408:对通过 AWGN信道后的信号以时隙为单位进行截取，截取时隙 0-3 , 在对信号进行截取时， 截取信号的总点数小于信号发生器内部存储容量。 S408: The signal after passing through the AWGN channel is intercepted in time slot units, and the time slot 0-3 is intercepted. When the signal is intercepted, the total number of intercepted signals is smaller than the internal storage capacity of the signal generator.
S409: 将上述信号转换成满足矢量信号发生器 ( VSG ) 4438C输入格式的 信号。 S409: Convert the above signal into a signal that satisfies the vector signal generator (VSG) 4438C input format.
S410: 矢量信号发生器（ VSG ) 4438C将输入的信号以 754MHz的频率和 - 1 OdB的幅度进行循环发送。 S410: Vector Signal Generator (VSG) The 4438C cyclically transmits the input signal at a frequency of 754 MHz and an amplitude of -1 OdB.
上述测试信号通过电缆输出给终端。 由此， 终端可以接收到一路受噪声干 扰的数据流。 由于数据流的格式已知， 可以进行误码率性能测试。 The above test signal is output to the terminal through a cable. Thus, the terminal can receive a data stream that is disturbed by noise. Since the format of the data stream is known, the bit error rate performance test can be performed.
如上所述， 首先，信号处理平台对输入的系统控制信息和数据流进行编码 和调制处理。 而后，信号截取转换装置对信号处理平台的输出信号以时隙为单 位进行截取， 并转换成满足矢量信号发生器输入格式的信号。 最后， 矢量信号 发生器将将输入信号以指定的频率和幅度循环发送， 并通过电缆输出给终端。 由此， 终端接收承载有系统控制信息和数据流两种信息的标准测试信号，对误 码率性能进行测试。 As described above, first, the signal processing platform encodes and modulates the input system control information and data stream. Then, the signal interception conversion device intercepts the output signal of the signal processing platform in units of time slots, and converts it into a signal satisfying the input format of the vector signal generator. Finally, the vector signal generator will cycle the input signal at the specified frequency and amplitude and output it to the terminal via the cable. Thus, the terminal receives a standard test signal carrying both system control information and data stream information, and tests the bit error rate performance.
本领域普通技术人员可以理解实现上述实施例方法携带的全部或部分 步骤是可以通过程序来指令相关的硬件完成， 所述的程序可以存储于一种 计算机可读存储介质中， 该程序在执行时， 包括方法实施例的步骤之一或 其组合。 A person skilled in the art can understand that all or part of the steps carried by the method of the foregoing embodiment can be completed by a program to instruct related hardware, and the program can be stored in a computer readable storage medium. , including one or a combination of the steps of the method embodiments.
另外， 在本发明各个实施例中的各功能单元可以集成在一个处理模块 中， 也可以是各个单元单独物理存在， 也可以两个或两个以上单元集成在 一个模块中。 上述集成的模块既可以釆用硬件的形式实现， 也可以釆用软 件功能模块的形式实现。 所述集成的模块如果以软件功能模块的形式实现 并作为独立的产品销售或使用时， 也可以存储在一个计算机可读取存储介 质中。In addition, each functional unit in each embodiment of the present invention may be integrated into one processing module, or each unit may exist physically separately, or two or more units may be integrated into one module. The above integrated modules can be implemented in the form of hardware or soft. The form of the functional module is implemented. The integrated modules, if implemented in the form of software functional modules and sold or used as separate products, may also be stored in a computer readable storage medium.
上述提到的存储介质可以是只读存储器， 磁盘或光盘等。 The above-mentioned storage medium may be a read only memory, a magnetic disk or an optical disk or the like.
以上所披露的仅为本发明的优选实施例， 当然不能以此来限定本发明 的权利保护范围。 可以理解， 根据本发明所附权利要求书中限定的实质和 范围所作的等同变化， 仍属于本发明所涵盖的范围。 The above disclosure is only a preferred embodiment of the present invention, and it is of course not possible to limit the scope of the present invention. It is to be understood that equivalent changes made in the spirit and scope of the invention are intended to be included within the scope of the invention.