Hao Ma

In this paper, we propose a multi-beam integrated radar and communication scheme using phased-array antenna, in which the same LFM-BPSK integrated waveform is used for both the radar and the communication beams. In the integrated beam design, the radar beam is periodically scanned in different directions for detection, and the communication beam is periodically manipulated in one direction for communication. The system’s beamforming uses adaptive beamforming technology to achieve radar echoes and communication reception. For the LFM-BPSK integrated waveform used by the system, we propose a method for estimating parameters during communication reception. Through simulation, the proposed beam-pattern design, adaptive beamforming, and parameter estimation scheme can achieve radar and communication functions using phased-array antennas.

The problem of orthogonal waveform construction in multiple input/multiple output (MIMO) radar communication integration greatly limits the realization of integration technology. In the unmanned aerial vehicle (UAV) MIMO antenna scenario, an orthogonal integrated waveform suitable for a MIMO antenna is designed using a sub−LFM−BPSK waveform combined with a chaotic spread spectrum code. After spread spectrum processing, each MIMO antenna transmits different communication data for orthogonal spread spectrum processing, which is suitable for the omnidirectional detection of MIMO application scenarios; moreover, the closed-form expressions of the integrated orthogonal waveform under certain constraints are derived. Finally, the simulation proves that the integrated orthogonal waveform set in the UAV MIMO scenario has excellent radar detection and communication capabilities.

Performing the high-precision Global Navigation Satellite System (GNSS) applications with low-cost antennas is an up-and-coming research field. However, the antenna-induced phase biases, i.e., phase center corrections (PCCs), of the low-cost antennas can be up to centimeters and need to be calibrated in advance. The relative field antenna calibration method is easy to conduct, but the classical procedure entails integer ambiguity resolution, which may face the problem of low success rate under the centimeter-level PCCs. In this contribution, we designed a relative field calibration method suitable for the low-cost GNSS antennas. The triple-differencing operations were utilized to eliminate the carrier-phase ambiguities and then construct PCC measurements; the time-differencing interval was set to a relatively long time span, such as one hour, and the reference satellite was selected according to the angular distance it passed over during a time-differencing interval. To reduce the effect of significant triple-differencing noise, a weight setting method based on the area of a spherical quadrilateral was proposed for the spherical harmonics fitting process. The duration of the data collection with respect to GPS and BDS was discussed. The performance of the proposed method was assessed with real GPS and BDS observations and a variety of simulated phase patterns, showing that calibration results could be obtained with millimeter-level accuracy. The impact of cycle slip and elevation mask angle on the calibration results was also analyzed.

Beam synthesis is a key technology in the radar communication integrated system. In this paper, phased array radar is used as the beam synthesis hardware basis of the radar communication integration. According to the functional requirements of integration., we set the radar main lobe and the communication main lobe for the integrated pattern; and then we set the direction parameters of the radar main lobe and the communication main lobe according to the requirements of radar detection and communication; and then minimize the peak value for the sidelobe objective. The integrated beam synthesis problem is constructed as a first-order convex optimization problem, and finally the beam synthesis problem is solved using the convex optimization toolbox. Through the simulation of uniform linear array elements, it is proved that when the method is used for beam synthesis design, the integrated system beam has lower side lobes under the condition of realizing radar beam and communication beams, and at the same time realizes the integrated system beam.

The existing joint radar-communication (JRC) based on linear frequency modulation (LFM) is imperfect because of high autocorrelation sidelobe and poor nearby target detection performance. This paper proposes a JRC signal based on the non-LFM (NLFM) wave by using minimum shift keying (MSK). Then, this paper analyzes the performance of ambiguity function (AF) characteristics, detection probability, time-frequency characteristics, and communication rate for the proposed JRC signal. It is concluded that the proposed JRC signal has both excellent radar and communication characteristics. Under the condition of low data volume, the simulation results illustrate that (i) compared with the existing LFM-MSK signal, our JRC signal’s sidelobe level of the time AF is significantly lower; the range resolution is improved significantly; (ii) the proposed JRC signal has no loss on velocity resolution and detection probability; and (iii) the proposed JRC signal has excellent time-frequency characteristics.

This paper investigates a novel design for joint radar-communication (JRC) waveform, which is capable of improving the network’s performance by solving the phase shift mutation of the Chirp-BPSK waveform. We aim for jointly designing chirp waveform and improving Binary Phase Shift Keying (BPSK), as well as the hybrid chaotic spread spectrum code (CSSC). As a benefit, the JRC waveform can be successfully decoded, and the accumulation of phase shift can be suppressed by hybrid CSSC. The detailed deduction on the short-time Fourier transform (STFT) of the JRC waveform is adopted to analyse the complicated AF characters. Our analytical results demonstrate that the proposed JRC signal has superior spectrum performance, ambiguity function (AF), and transmission rate than conventional Chirp and Chirp-BPSK waveform. Numerical results are provided to confirm that (i) the proposed waveform is capable of providing better communication and radar performance; (ii) the performance of AF is not affected by the transmission rate for the proposed waveform.