Disclosure of Invention
In view of the above, the invention provides a micro-deformation telemetry system and a method based on a wireless synchronization technology, which can accurately and efficiently monitor the micro-deformation of a building in real time, and can effectively solve the problems of low monitoring precision, complex equipment and the like in the prior art.
Specifically, the method comprises the following technical scheme:
a micro-deformation telemetry system based on a wireless synchronization technology comprises a plurality of monitoring points 1 and a remote measuring station 2 which are arranged on a measured object;
the monitoring point 1 is composed of a spread spectrum modulation frequency multiplication forwarding circuit 11 and a wireless synchronous pulse receiving circuit 12; the station 2 is composed of a spread spectrum demodulation displacement resolving circuit 21 and a wireless synchronous pulse transmitting circuit 22;
the station 2 generates a radio frequency local oscillation signal with frequency fR1 As radio frequency carrier signals and transmitting to a monitoring point 1; the station 2 uses a wireless synchronous pulse transmitting circuit 22 to transmit a wireless synchronous pulse signal to the monitoring point 1; the monitoring point 1 carries out frequency multiplication processing on the received radio frequency carrier signal to obtain a carrier signal after coherent frequency conversion, and the frequency of the carrier signal is fR2 ＝2fR1 The method comprises the steps of carrying out a first treatment on the surface of the The wireless synchronization pulse receiving circuit 12 extracts a first synchronization pulse signal 1109, under the control of the synchronization pulse signal, generates a pseudo code signal identifying a monitoring point by using the first pseudo code generating circuit 1108, and uses the pseudo code signal to spread spectrum modulate a carrier signal after coherent frequency conversion, and then transmits the carrier signal to the station 2; the station 2 receives the echo signal emitted by the monitoring point 1 and the frequency is fR1 Performing frequency multiplication processing on the local radio frequency local oscillation signal to obtain a frequency fR2 ＝2fR1 The radio frequency local oscillation signal is used for carrying out quadrature down-conversion on the echo signal from the monitoring point 1 received by the measuring station 2 and converting the echo signal into a baseband signal; the station 2 outputs a second synchronization pulse signal 2112 by using the wireless synchronization pulse transmitting circuit 22, and uses under the control of the synchronization pulse signalThe second pseudo code generating circuit 2110 regenerates the pseudo code signal of the monitoring point, then performs correlation despreading on the baseband signal obtained by the quadrature down-converter, and then sends the baseband signal to the displacement calculating circuit 2111 to calculate the displacement of the monitoring point.
Further, the spread spectrum modulation frequency multiplication repeater circuit 11 is composed of a first dual-frequency antenna 1101, a first band-pass filter 1102, a first low noise amplifier 1103, a first frequency multiplier 1104, a mixer 1105, a second band-pass filter 1106, a second power amplifier 1107 and a first pseudo code generation circuit 1108; the first pseudo code generating circuit 1108 is controlled by a first synchronization pulse signal 1109;
wherein: the first dual-band antenna 1101 is sequentially connected to a first band-pass filter 1102, a first low noise amplifier 1103, and a first frequency multiplier 1104, and the mixer 1105 filters a signal in the first band-pass filter 1102, then enters the first low noise amplifier 1103, passes through the first frequency multiplier 1104, then is fed into the mixer 1105, mixes with a pseudo code generated by the first pseudo code generating circuit 1108 in the mixer 1105, then outputs the mixed signal to the second band-pass filter 1106, amplifies the mixed signal by the second power amplifier 1107, and then transmits the amplified signal.
Further, the spread spectrum demodulation shift calculating circuit 21 is composed of a second dual-frequency antenna 2101, a third power amplifier 2102, a third band-pass filter 2103, a radio frequency local oscillation source 2104, a second frequency multiplier 2105, a fourth band-pass filter 2106, a fourth low noise amplifier 2107, a quadrature down converter 2108, a correlation despreading circuit 2109, a second PN code generating circuit 2110 and a shift amount calculating circuit 2111, wherein the second pseudo code generating circuit 2110 is controlled by a second synchronous pulse signal 2112;
wherein: the radio frequency local oscillation source 2104 is sequentially connected with the third band-pass filter 2103, the third power amplifier 2102 and the second dual-frequency antenna 2101, and radio frequency carrier signals generated by the radio frequency local oscillation source 2104 are radiated through the second dual-frequency antenna 2101 after being filtered and amplified; the second dual-frequency antenna 2101 is sequentially connected with the fourth band-pass filter 2106, the fourth low-noise amplifier 2107 and the quadrature down-converter 2108, and echo signals received by the second dual-frequency antenna 2101 are filtered and amplified and then sent to the quadrature down-converter 2108; the radio frequency carrier wave generated by the radio frequency local oscillation source 2104 is sent to the quadrature down converter 2108 after passing through the second frequency multiplier 2105, so as to obtain a baseband signal, the baseband signal is sent to the relevant despreading circuit 2109, the second pseudo code generating circuit 2110 locally regenerates the pseudo code signal at the monitoring point, the pseudo code signal is sent to the relevant despreading circuit 2109, and the relevant despreading circuit 2109 carries out relevant despreading processing on the baseband signal, and then the baseband signal is input to the displacement calculating circuit 2111.
Further, the wireless synchronization pulse receiving circuit 12 is composed of a receiving antenna 1201, a power divider 1202, a fifth bandpass filter 1203, a fifth low noise amplifier 1204, a first envelope detector 1205, a sixth bandpass filter 1206, a sixth low noise amplifier 1207, a second envelope detector 1208, a comparator 1209, a lead matching filter 1210, an output matching filter 1211, a lag matching filter 1212, a synchronization pulse decision circuit 1213, and a first delay circuit 1214; the first delay circuit 1214 sends out a first synchronization pulse signal 1109;
wherein: after the receiving antenna 1201 receives the signal, the signal enters the power divider 1202, the signal is divided into two paths, one path passes through the fifth band-pass filter 1203, the fifth low noise amplifier 1204 and the first envelope detector 1205, the other path passes through the sixth band-pass filter 1206, the sixth low noise amplifier 1207 and the second envelope detector 1208, the two paths of signals enter the comparator 1209, the signal output from the comparator 1209 passes through the lead matching filter 1210, the output matching filter 1211 and the lag matching filter 1212, and then enters the synchronous pulse decision circuit 1213, and the signal output from the synchronous pulse decision circuit 1213 enters the first delay circuit 1214.
Further, the wireless synchronization pulse transmitting circuit 22 is composed of a transmitting antenna 2201, a combiner 2202, a first switch 2203, a first carrier wave generator 2204, a third pseudo code generating circuit 2205, a inverting circuit 2206, a second switch 2207, a second carrier wave generator 2208, a synchronization pulse generating circuit 2209 and a second delay circuit 2210; the second delay circuit 2210 outputs a second synchronization pulse signal 2112;
wherein: the first carrier generator 2204 is connected to the first switch 2203, and the second carrier generator 2208 is connected to the second switch 2207; the synchronization pulse generation circuit 2209 is connected to the second delay circuit 2210 and the third pseudo code generation circuit 2205, respectively; the third pseudo code generating circuit 2205 is connected to the first switch 2203 and connected to the second switch 2207 through the inverting circuit 2206; the first switch 2203 and the second switch 2207 are respectively connected to the combiner 2202, and the signals are finally transmitted through the combiner 2202 and then through the transmitting antenna 2201.
Further, the pseudo code is m sequence or Gold code.
The invention also provides a micro-deformation telemetry method based on the wireless synchronization technology, which comprises the following steps:
s1: the measuring station 2 generates a radio frequency local oscillation signal with the frequency fR1 As radio frequency carrier signals and transmitting to a monitoring point 1;
s2: the station 2 uses the wireless synchronous pulse transmitting circuit 22 to transmit the wireless synchronous pulse signal to the monitoring point;
s3: the monitoring point 1 carries out frequency multiplication processing on the received radio frequency carrier signal to obtain a carrier signal after coherent frequency conversion, and the frequency of the carrier signal is fR2 ＝2fR1 ；
S4: the wireless synchronous pulse receiving circuit 12 extracts a first synchronous pulse signal 1109, generates a pseudo code signal for identifying a monitoring point under the control of the synchronous pulse signal, uses the pseudo code signal to spread spectrum modulate a carrier signal after coherent frequency conversion, and then transmits the carrier signal to the station 2;
s5: the station 2 receives the echo signal emitted by the monitoring point 1 and the frequency is fR1 Performing frequency multiplication processing on the local radio frequency local oscillation signal to obtain a frequency fR2 ＝2fR1 The radio frequency local oscillation signal is used for carrying out quadrature down-conversion on the echo signal from the monitoring point 1 received by the measuring station 2 and converting the echo signal into a baseband signal;
s6: the station 2 uses a second synchronous pulse signal 2112 output by the wireless synchronous pulse transmitting circuit to control a second pseudo code generating circuit to regenerate a pseudo code signal of the monitoring point, then carries out correlation despreading on a baseband signal obtained by the quadrature down converter, and then sends the baseband signal to a displacement calculating circuit 2111 to calculate the displacement of the monitoring point.
Further, in step S4, the wireless synchronization pulse receiving circuit 12 is configured by a receiving antenna 1201, a power divider 1202, a fifth bandpass filter 1203, a fifth low noise amplifier 1204, a first envelope detector 1205, a sixth bandpass filter 1206, a sixth low noise amplifier 1207, a second envelope detector 1208, a comparator 1209, a lead matching filter 1210, an output matching filter 1211, a lag matching filter 1212, a synchronization pulse decision circuit 1213, and a first delay circuit 1214; the first delay circuit 1214 sends out a first synchronization pulse signal 1109; after the receiving antenna 1201 receives the signal, the signal enters the power divider 1202, after the signal is divided into two paths, one path of the signal respectively passes through the fifth band-pass filter 1203, the fifth low noise amplifier 1204 and the first envelope detector 1205, the other path of the signal respectively passes through the sixth band-pass filter 1206, the sixth low noise amplifier 1207 and the second envelope detector 1208, the two paths of the signal enter the comparator 1209, and the signal output from the comparator 1209 respectively passes through the advanced matching filter 1210, the output matching filter 1211 and the lag matching filter 1212 and then enters the synchronous pulse decision circuit 1213, and the signal output from the synchronous pulse decision circuit 1213 enters the first delay circuit 1214.
The invention has the beneficial effects that: (1) Each monitoring point is an independent active forwarding circuit, cable connection is not needed between the monitoring points and the measuring stations, and a monitoring point circuit is not needed to be installed on the datum point, so that the flexibility of the system is improved; (2) The monitoring point and the station point realize pseudo code synchronization by using the synchronous pulse signals, a closed-loop pseudo code tracking loop is not needed, and the reliability of the system is improved; (3) The monitoring points and the measuring stations adopt different-frequency receiving and transmitting technology, so that the problem of continuous wave radar receiving and transmitting crosstalk is effectively solved, and the system has the advantage of long measuring distance.
Detailed Description
Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings.
The invention provides a micro-deformation telemetry system based on a wireless synchronization technology, which consists of a plurality of monitoring points 1 and a plurality of measuring stations 2. The monitoring point 1 is composed of a spread spectrum modulation frequency multiplication forwarding circuit 11 and a wireless synchronous pulse receiving circuit 12; the station 2 is composed of a spread spectrum demodulation displacement resolving circuit 21 and a wireless synchronization pulse transmitting circuit 22. The station 2 generates and transmits a radio frequency carrier signal and a wireless synchronous pulse signal to the monitoring point 1; the monitoring point 1 receives the radio frequency carrier signal to perform frequency multiplication processing, extracts a wireless synchronous pulse signal, generates a monitoring point pseudo code, performs spread spectrum modulation on the frequency-multiplied radio frequency carrier signal, and transmits the frequency-multiplied radio frequency carrier signal to the monitoring point 2; the station 2 uses the frequency-doubled radio frequency carrier signal as a local oscillation signal to carry out quadrature down-conversion on the echo signal, regenerates the pseudo code of the monitoring point under the control of the synchronous pulse signal output by the wireless synchronous pulse transmitting circuit 22, carries out correlation despreading on the baseband signal, and calculates the displacement of each monitoring point.
Fig. 1 is a schematic diagram of a measurement system according to the present invention, and as shown in the drawing, the measurement system provided by the present invention is a micro-deformation telemetry system based on a wireless synchronization technology, and the measurement system is composed of a plurality of monitoring points 1 installed on a measured object and a remote measuring station 2. The monitoring point 1 is composed of a spread spectrum modulation frequency multiplication forwarding circuit 11 and a wireless synchronous pulse receiving circuit 12; the station 2 is composed of a spread spectrum demodulation displacement resolving circuit 21 and a wireless synchronization pulse transmitting circuit 22. The measuring station 2 generates a radio frequency local oscillation signal with the frequency fR1 As radio frequency carrier signals and transmitting to a monitoring point 1; the station 2 uses the wireless synchronous pulse transmitting circuit 22 to transmit the wireless synchronous pulse signal to the monitoring point; the monitoring point 1 carries out frequency multiplication processing on the received radio frequency carrier signal to obtain a carrier signal after coherent frequency conversion, and the frequency of the carrier signal is fR2 ＝2fR1 The method comprises the steps of carrying out a first treatment on the surface of the The wireless synchronous pulse receiving circuit 12 extracts the synchronous pulse signal, generates a pseudo code signal for identifying the monitoring point under the control of the synchronous pulse signal, uses the pseudo code signal to spread spectrum modulate the carrier signal after coherent frequency conversion, and then transmits the carrier signal to the measuring station 2; the station 2 receives the echo signal emitted by the monitoring point 1 and the frequency is fR1 Performing frequency multiplication processing on the local radio frequency local oscillation signal to obtain a frequency fR2 ＝2fR1 The radio frequency local oscillation signal is used for carrying out quadrature down-conversion on the echo signal from the monitoring point 1 received by the measuring station 2 and converting the echo signal into a baseband signal; the station 2 uses the synchronous pulse signal output by the wireless synchronous pulse transmitting circuit to control the local monitoring point second pseudo code generating circuit to regenerate the monitoring point pseudo code, then carries out correlation despreading on the baseband signal obtained by the quadrature down converter, and then sends the baseband signal to the displacement calculating circuit 2111 to calculate the displacement of the monitoring point.
Fig. 2 is a block diagram of a spread spectrum modulation frequency multiplication repeater circuit according to the present invention, and as shown in the drawing, the spread spectrum modulation frequency multiplication repeater circuit 11 is composed of a first dual-band antenna 1101, a first band-pass filter 1102, a first low noise amplifier 1103, a first frequency multiplier 1104, a mixer 1105, a second band-pass filter 1106, a second power amplifier 1107 and a first pseudo code generation circuit 1108; the first pseudo code generating circuit 1108 is controlled by a first synchronization pulse signal 1109.
Fig. 3 is a block diagram showing a configuration of a spread spectrum demodulation shift calculating circuit according to the present invention, wherein the spread spectrum demodulation shift calculating circuit 21 is composed of a second dual-band antenna 2101, a third power amplifier 2102, a third band-pass filter 2103, a radio frequency source 2104, a second frequency multiplier 2105, a fourth band-pass filter 2106, a fourth low noise amplifier 2107, a quadrature down converter 2108, a correlation despreading circuit 2109, a second PN code generating circuit 2110 and a shift amount calculating circuit 2111, and the second pseudo code generating circuit 2110 is controlled by a second synchronization pulse signal 2112.
Fig. 4 is a block diagram showing a structure of a wireless synchronization pulse receiving circuit according to the present invention, wherein the wireless synchronization pulse receiving circuit 12 is composed of a receiving antenna 1201, a power divider 1202, a fifth bandpass filter 1203, a fifth low noise amplifier 1204, a first envelope detector 1205, a sixth bandpass filter 1206, a sixth low noise amplifier 1207, a second envelope detector 1208, a comparator 1209, a lead matching filter 1210, an output matching filter 1211, a lag matching filter 1212, a synchronization pulse decision circuit 1213, and a first delay circuit 1214, and the first delay circuit 1214 sends out a first synchronization pulse 1109. The wireless synchronization pulse receiving circuit 12 may also receive remote control command data such as turning on or off the monitor point, setting the transmit power of the monitor point, and the delay time of the first delay circuit 1214.
Fig. 5 is a block diagram of a wireless synchronization pulse transmitting circuit according to the present invention, where as shown in the drawing, a wireless synchronization pulse transmitting circuit 22 is composed of a transmitting antenna 2201, a combiner 2202, a first switch 2203, a first carrier generator 2204, a third pseudo code generating circuit 2205, a negating circuit 2206, a second switch 2207, a second carrier generator 2208, a synchronization pulse generating circuit 2209, and a second delay circuit 1210; the second delay circuit 1210 sends a second synchronization pulse signal 2112. The wireless synchronization pulse transmitting circuit 22 may also transmit remote control command data such as turning on or off the monitor point, setting the transmit power of the monitor point, and the delay time of the first delay circuit 1214.
Assume that the distance between the ith monitoring point 1 and the measuring station 2 is Ri I=1, 2, …, n; let the maximum distance be Rmax The second delay circuit 2208 should delay time to be set to: τ2 ＝(Rmax C), where c is the electromagnetic wave propagation speed, the first delay circuit 1214 delay time should be set to:if the distance between each monitoring point 1 and the measuring station 2 is relatively close, the delay time of the two delay circuits is approximately 0, and the two delay circuits can be omitted.
Assume that the pseudo code rate is fpn The chip width is Tpn ＝(1/fpn ) Code length is M, pseudo code period T1 ＝(M·Tpn ) The method comprises the steps of carrying out a first treatment on the surface of the Assume that the clock frequencies of the first, second and third pseudo code generating circuits are fs ＝(K·fpn ) K is an oversampling multiple, and the width of the synchronous pulse is TPsync ＝(Tpn K) the repetition period of the synchronization pulse is T2 ＝(M·Tpn ) And pseudo code period T1 The same applies.
Assume that the first carrier signal generated by the first carrier generator 2204 has a frequency fc1 With a bandwidth of B, the second carrier signal generated by the second carrier generator 2208 has a frequency of fc2 The bandwidth is B, the difference between the two carrier frequencies is Deltafc ＝|fc1 -fc2 |，Δfc ＞＞B，B＞＞fpn 。
Assuming that the data signal generated by the third pseudo-code generating circuit 2205 is pseudo-code PN0, the output signal of the comparator 1209 is Y0 Y is then0 A pseudo code PN0 generated for the third pseudo code generating circuit 2205, that is, a data signal transmitted by the wireless synchronization pulse transmitting circuit is demodulated; the coefficients of the lead matched filter 1210, the coefficients of the output matched filter 1211, and the tap coefficients of the lag matched filter 1212 are the inverse of the pseudo code PN0, and the lead-lag is half a chip width, Δt= (T)pn 2); assume that the output signal of the lead matched filter 1210 is Y1 The output signal of the output matched filter 1211 is Y2 The output signal of the lag matched filter 1212 is Y3 When the following condition is satisfied: y is Y2 >(M+1)/2, and (Y)1 -Y3 ) k.2.k.m+1)/K, k.epsilon.1, 2; the sync pulse decision circuit 1213 outputs a pulse signal to the first delay circuit 1214 to generate a first sync pulse signal 1109. By the combined use of the wireless synchronous pulse receiving circuit shown in fig. 4 and the wireless synchronous pulse transmitting circuit shown in fig. 5, precise (or high-precision) remote pulse synchronization can be realized between monitoring points and between the monitoring points and the measuring points, and the circuit has reliable working performance.
The displacement calculation circuit 2111 calculates the phase angle of the baseband signal of the i-th monitoring point 1 obtained by despreading, and calculates the phase difference, Φ, of the reciprocating electromagnetic wave signali ＝2π·(2fR1 ·2Ri ) C; then calculate the phase difference phii The variation delta phi of (2)i To calculate the displacement DeltaRi ＝Δφi /(8π)λR1 。λR1 ＝c/fR1 For measuring the wavelength of the radio frequency carrier signal emitted by station 2.
Finally, it is noted that the above-mentioned preferred embodiments illustrate rather than limit the invention, and that, although the invention has been described in detail with reference to the above-mentioned preferred embodiments, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the scope of the invention as defined by the appended claims.