A communication and sensing integrated system capable of realizing two-dimensional positioning

Abstract

The present invention belongs to the technical field of wireless communication and sensing positioning, and discloses a communication and sensing integrated system capable of realizing two-dimensional positioning, which includes four major parts: a transmitting end, a transmission end, a communication receiving end, and a sensing receiving end; First, single I / Q modulator is used to achieve independent sideband modulation, and the optical signals of the upper and lower sidebands carry different signals respectively; Then, it is frequency-mixed with the LFM odd-order sideband signal generated by the intensity modulator IM to generate a terahertz integrated electrical signal modulated by MQAM-LFM, realizing ranging, angle measurement, and communication functions. The present invention adopts the above-mentioned communication and sensing integrated system capable of realizing two-dimensional positioning, and simultaneously has the functions of high-speed communication, high-precision ranging and angle measurement, solves the problem that high-speed communication and high-precision sensing cannot be achieved by current waveform technology, and provides a solution for the realization of two-dimensional coordinate measurement in the current communication and sensing integrated system.

Description

Technical Field

[0001] The present invention relates to the technical field of wireless communication and sensing positioning, and particularly to a communication and sensing integrated system capable of realizing two-dimensional positioning. Background Art

[0002] Currently, the research on communication and sensing integrated systems mainly focuses on two aspects. One is the integrated signal based on multiplexing technology, and the other is the integrated signal using waveform design. Although the former can achieve high-rate communication and high-precision sensing, it does not utilize the same spectrum resources, resulting in low spectrum utilization. The latter can support both communication and sensing functions on the same spectrum and the same device simultaneously, but it cannot meet the requirements of high-rate communication and high-precision sensing demanded by 5G / 6G networks.

[0003] Most of the current existing communication and sensing integrated systems adopt single-input single-output technology (SISO) and achieve the sensing of distance information. However, due to the use of only a single transmitting antenna and a single receiving antenna, the existing systems cannot achieve the sensing of two-dimensional coordinates. Moreover, SISO technology also greatly limits the communication capacity and spectrum efficiency of the system.

[0004] Therefore, the present invention proposes a communication and sensing integrated system capable of realizing two-dimensional positioning, which solves the problem that high-rate communication and high-precision sensing cannot be achieved by using waveform technology at present, and provides a solution for the realization of two-dimensional coordinate measurement in the current communication and sensing integrated system. Summary of the Invention

[0005] The object of the present invention is to provide a communication and sensing integrated system capable of realizing two-dimensional positioning. The MIMO technology is used in the communication and sensing integrated system, and a single I / Q modulator and a single intensity modulator IM are utilized to implement an integrated system of MIMO communication and sensing integration. The method of beating a multi-order sideband LFM optical signal and an MQAM optical signal is adopted to generate a terahertz communication and sensing integrated signal. This system simultaneously has the functions of high-rate communication, high-precision ranging and angle measurement, solves the problem that high-rate communication and high-precision sensing cannot be achieved by using waveform technology at present, and provides a solution for the realization of two-dimensional coordinate measurement in the current communication and sensing integrated system.

[0006] To achieve the above object, the present invention provides a communication and sensing integrated system capable of realizing two-dimensional positioning, which includes four major parts: a transmitting end, a transmission end, a communication receiving end, and a sensing receiving end;

[0007] First, use a single I / Q modulator to achieve independent sideband modulation, where the optical signals of the upper and lower sidebands carry different signals respectively; then, beat with the LFM odd-order sideband signals generated by the intensity modulator IM to generate a terahertz integrated electrical signal modulated by MQAM-LFM, realizing ranging, angle measurement, and communication functions.

[0008] Preferably, at the transmitter end of the system, the operating wavelength of the external cavity laser ECL1 is 1553.60 nm, the linewidth is 10 kHz, and the output power is 13 dBm; the continuous wave light source is coupled into the I / Q modulator, where the sub-Mach-Zehnder modulators of the I / Q modulator all operate in the center carrier suppression mode, and the half-wave voltage of the Mach-Zehnder modulator is 4 V, the insertion loss is 6 dB, and the extinction ratio is 30 dB.

[0009] Preferably, after the optical signal is transmitted in the single-mode fiber for 10 km, the erbium-doped fiber amplifier EDFA is used to compensate for the optical power loss of the optical signal during fiber transmission, and finally the upper and lower sidebands of the optical signal are filtered out by the optical filter OF1 respectively.

[0010] Preferably, the operating wavelength of the external cavity laser ECL2 is 1555.90 nm, and the output power and linewidth are 6 dBm and 10 kHz respectively; the continuous wave light source emitted by the external cavity laser ECL2 is coupled into the intensity modulator IM and driven by the linear frequency modulation signal LFM signal; among them, the parameters of the intensity modulator IM are the same as those of the sub-Mach-Zehnder modulators of the I / Q modulator, and the operating mode of the intensity modulator IM is set to the center carrier suppression mode; by adjusting the driving voltage of the intensity modulator IM, the optical power of the ±3-order sidebands of the output signal of the intensity modulator IM is maximized, and the ±3-order sidebands of the optical signal output by the intensity modulator IM are filtered out by the optical filter OF2 respectively.

[0011] Preferably, during the transmission process, the optical signals output by the two optical filters are coupled through two couplers respectively, and the coupled optical signal is converted into an electrical signal by the photodiode PD; among them, the responsivity of the photodiode PD is 0.4 A / W, the frequency interval between the two optical carriers is 285 GHz, the center carrier of the integrated signal generated after photoelectric conversion is in the 285 GHz frequency band, and the generated terahertz signal is transmitted into free space through two transmitting antennas.

[0012] Preferably, for the communication receiving part, each set of transceiver antennas is integrated by a pair of special lenses and antennas; the terahertz band signals are received by two different antennas respectively and down-converted to the IF domain. The operating frequency of the electrical local oscillator ELO1 after frequency multiplication is 276 GHz, and the intermediate frequency signal is sent into an oscilloscope OSC with a 3 dB bandwidth of 30 GHz and a sampling rate of 64 GSa / s, and the signal is restored through digital signal processing.

[0013] Preferably, the digital signal processing includes down-conversion, de-chirping, Schmidt orthogonalization, clock recovery, cascaded multi-mode equalization algorithm, fourth-order frequency offset estimation, and blind phase search carrier phase estimation.

[0014] Preferably, at the sensing end, the terahertz signal is reflected by the target, and the echo signal is received by the radar receiving antenna. After passing through a 20dB low-noise amplifier and down-conversion, it is captured and collected by an oscilloscope, and then the sensing information and angle information are extracted through a pulse compression algorithm in the digital domain.

[0015] Therefore, the present invention adopts the above-mentioned communication and sensing integrated system capable of realizing two-dimensional positioning, and the beneficial effects are as follows:

[0016] (1) The system proposed by the present invention simultaneously has high-speed communication, high-precision ranging, and a certain angle measurement function. Thanks to the MIMO technology, the communication end can achieve higher communication rate and spectrum efficiency. At the same time, in terms of sensing, not only can the measurement of one-dimensional coordinates be realized, but also the measurement of two-dimensional coordinates can be realized.

[0017] (2) The optical signal generated by SSB modulation in the present invention can resist the frequency-selective attenuation effect caused by fiber dispersion, and has higher spectrum efficiency. Moreover, all modulators in the system work in the carrier suppression mode, with high modulation efficiency.

[0018] (3) The present invention uses a single intensity modulator IM to generate an LFM optical signal with multiple sidebands, and flexibly generates terahertz integrated signals with different bandwidths, different chirp slopes, and different frequencies by using the heterodyne beat frequency technology.

[0019] The technical solution of the present invention will be further described in detail below with reference to the drawings and embodiments. Description of the Drawings

[0020] Figure 1 It is a block diagram of a communication and sensing integrated system capable of realizing two-dimensional positioning according to the present invention. Detailed Embodiments

[0021] The technical solution of the present invention will be further described below with reference to the drawings and embodiments.

[0022] As Figure 1 shown, a communication and sensing integrated system capable of realizing two-dimensional positioning according to the present invention includes four major parts: a transmitting end, a transmission end, a communication receiving end, and a sensing receiving end.

[0023] First, single-sideband modulation is achieved using a single I / Q modulator, and the optical signals of the upper and lower sidebands carry different signals respectively; then, beat frequency is generated with the LFM odd-order sideband signals generated by the intensity modulator IM to generate a terahertz integrated electrical signal modulated by MQAM-LFM. The system proposed by the present invention can simultaneously achieve ranging, angle measurement, and communication functions.

[0024] Embodiment

[0025] As Figure 1 shown, a communication and sensing integrated system capable of two-dimensional positioning according to the present invention has the following specific implementation process:

[0026] At the transmitter end of the system, the working wavelength of the external cavity laser ECL1 is 1553.60 nm, the line width is 10 kHz, and the transmission power is 13 dBm. The continuous wave light source is coupled into the I / Q modulator, where the sub-MZMs (Mach-Zehnder modulators) of the I / Q modulator all work in the center carrier suppression mode, and the half-wave voltage of the MZM is 4 V, the insertion loss is 6 dB, and the extinction ratio is 30 dB.

[0027] After the optical signal is transmitted in the single-mode fiber for 10 km, the erbium-doped fiber amplifier EDFA is used to compensate for the optical power lost during the transmission of the optical signal in the fiber. Finally, the upper and lower sidebands of the optical signal are filtered out by the optical filter OF1 respectively.

[0028] The working wavelength of the external cavity laser ECL2 is 1555.90 nm, and the transmission power and line width are 6 dBm and 10 kHz respectively. The continuous wave light source emitted by the external cavity laser ECL2 is coupled into the intensity modulator IM and driven by the linear frequency modulation signal LFMsignal. Among them, the parameters of the intensity modulator IM are the same as those of the sub-MZM of the I / Q modulator, and the working mode of the intensity modulator IM is also set to the center carrier suppression mode. In addition, by adjusting the driving voltage of the intensity modulator IM, the optical power of the ±3 order sidebands of the output signal of the intensity modulator IM is maximized. Finally, the ±3 order sidebands of the optical signal output by the intensity modulator IM are filtered out by the optical filter OF2 respectively.

[0029] During the transmission process, the optical signals output by the two optical filters are coupled through two couplers respectively, and the coupled optical signal is converted into an electrical signal by the photodiode PD. Among them, the responsivity of the photodiode PD is 0.4 A / W, the frequency interval between the two optical carriers is 285 GHz, the center carrier of the integrated signal generated after photoelectric conversion is in the 285 GHz frequency band, and the generated terahertz signal is transmitted into the free space through two transmitting antennas.

[0030] For the communication receiving part, each set of transceiver antennas is integrated by a pair of special lenses and antennas. The diameter of Lens 1 is 10 cm and the focal length is about 20 cm; the diameter of Lens 2 is 60 cm and the focal length is about 100 cm. The combined gain of HA1 and Lens1 is about 35 dBi; the combined gain of HA2 and Lens2 is about 55 dBi.

[0031] On the communication receiver side, the terahertz band signals are received by two different sets of antennas respectively and down-converted to the IF domain. The operating frequency of the electrical local oscillator ELO1 after frequency multiplication is 276 GHz. The intermediate frequency signal is sent into an oscilloscope OSC with a 3 dB bandwidth of 30 GHz and a sampling rate of 64 GSa / s. Subsequently, signal recovery is performed through digital signal processing (DSP), and the DSP includes down-conversion, de-chirping, Schmidt (GSOP) orthogonality, clock recovery, cascaded multi-mode equalization algorithm (CMMA), quartic frequency offset estimation (FOE), and blind phase search carrier phase estimation (BPS).

[0032] At the sensing end, the terahertz signal is reflected by the target, and the echo signal is received by the radar receiving antenna. After passing through a 20 dB low-noise amplifier and down-conversion, it is captured and collected by the oscilloscope, and then the sensing information and angle information are extracted through the pulse compression algorithm in the digital domain.

[0033] Therefore, the present invention adopts the above-mentioned communication and sensing integrated system capable of two-dimensional positioning, which has high-speed communication, high-precision ranging, and a certain angle measurement function at the same time. Thanks to the MIMO technology at the communication end, higher communication rate and spectral efficiency can be achieved; at the same time, in terms of sensing, not only the measurement of one-dimensional coordinates can be realized, but also the measurement of two-dimensional coordinates can be realized. The optical signal generated by the SSB modulation used in the present invention can resist the frequency-selective attenuation effect caused by fiber dispersion, and has higher spectral efficiency. Moreover, all modulators in the system operate in the carrier suppression mode, with high modulation efficiency. The present invention uses a single intensity modulator IM to generate an LFM optical signal with multiple sidebands, and flexibly generates terahertz integrated signals with different bandwidths, different chirp slopes, and different frequencies by using the heterodyne beat frequency technology.

[0034] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that they can still modify or equivalently replace the technical solutions of the present invention, and these modifications or equivalent replacements cannot make the modified technical solutions deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A communication and perception integrated system capable of achieving two-dimensional positioning, characterized in that: It includes four parts: the transmitting end, the transmitting end, the communication receiving end and the sensing receiving end; First, a single I / Q modulator is used to realize independent sideband modulation, and the optical signals of the upper and lower sidebands carry different signals respectively. Then, the beat frequency of the LFM odd-order sideband signal generated by the intensity modulator IM generates an integrated terahertz electrical signal of MQAM-LFM modulation, realizing the functions of ranging, angle measurement and communication. At the transmitting end of the system, the operating wavelength of the external cavity laser ECL1 is 1553.60nm, the line width is 10kHz, and the transmitting power is 13dBm; the continuous wave light source is coupled into the I / Q modulator, where the sub-Mach Zehnder modulators of the I / Q modulator all work in the center carrier suppression mode, and the half-wave voltage of the Mach Zehnder modulator is 4V, the insertion loss is 6dB, and the extinction ratio is 30dB; After the optical signal is transmitted for 10 km in the single-mode optical fiber, the optical power lost in the optical signal transmission in the optical fiber is compensated by the erbium-doped fiber amplifier EDFA, and finally the upper and lower sidebands of the optical signal are filtered out respectively by the optical filter OF1; The working wavelength of the external cavity laser ECL2 is 1555.90nm, and the emission power and linewidth are 6dBm and 10kHz respectively; the continuous wave light source emitted by the external cavity laser ECL2 is coupled into the intensity modulator IM and driven by the linear frequency modulation signal LFMsignal; wherein the parameters of the intensity modulator IM are the same as the sub-Mach Zehnder modulator parameters of the I / Q modulator, and the working mode of the intensity modulator IM is set to the center carrier suppression mode; by adjusting the driving voltage of the intensity modulator IM, the ±3rd order sideband optical power of the output signal of the intensity modulator IM is maximized, and the ±3rd order sidebands of the optical signal output by the intensity modulator IM are filtered out respectively by the optical filter OF2.

2. The communication and perception integrated system capable of realizing two-dimensional positioning according to claim 1, characterized in that: During the transmission process, the optical signals output by the two optical filters are coupled respectively through two couplers, and the coupled optical signals are converted into electrical signals through the photodiode PD; wherein, the responsivity of the photodiode PD is 0.4A / W, the frequency interval between the two optical carriers is 285GHz, and the central carrier of the integrated signal generated after the photoelectric conversion is in the 285GHz frequency band, and the generated terahertz signal is transmitted into the free space through two transmitting antennas.

3. The communication and perception integrated system capable of realizing two-dimensional positioning according to claim 2, characterized in that: For the communication receiving part, each set of transmitting and receiving antennas is integrated with a pair of special lenses and antennas; the terahertz band signal is received by two different sets of antennas and down-converted to the IF domain. The operating frequency of the electrical local oscillator ELO1 is 276GHz after frequency multiplication. The intermediate frequency signal is sent to the oscilloscope OSC with a 3dB bandwidth of 30GHz and a sampling rate of 64GSa / s, and the signal is recovered through digital signal processing.

4. The communication and perception integrated system capable of realizing two-dimensional positioning according to claim 3, characterized in that: Digital signal processing includes down-conversion, de-chirping, Schmidt orthogonalization, clock recovery, cascaded multimode equalization algorithm, quartic frequency offset estimation and blind phase search carrier phase estimation.

5. The communication and perception integrated system capable of realizing two-dimensional positioning according to claim 4, characterized in that: At the sensing end, the terahertz signal is reflected by the target, and the echo signal is received by the radar receiving antenna. After passing through a 20dB low-noise amplifier and down-conversion, it is captured and collected by an oscilloscope, and then the perception information and angle information are extracted in the digital domain through a pulse compression algorithm.

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