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With the development of science and requirement, Integration of Communication and Radar with properties of more functions, lower buck and safety is becoming a trend and draws more attention of researchers. Current researches are focusing on communication or radar respectively or just focusing on signal generation. This paper proposes a solution of integrated system for SAR radar communication based on OFDM techniques in high speed scenario. The receiver can reconstruct the reference signal which is adopted for radar pulse compression procedure by communication system directly. In high speed scenario, channel response changes fast, comb type pilots and channel estimation are added to equalize the channel response to reduce bit-error-rate in communication system. Finally, the simulation are used to validate the performance of the proposed algorithm.

In bistatic SAR, range is difficult to be linearized for the complicated geometry. In this paper, comparing to monostatic SAR, a modified range direction is derived based on vector analysis. The scatters along this direction will be imaged to the same azimuth cell which is important for the nonlinear chirp scaling (NLCS) algorithm. Simulated results are proposed to validate the proposed algorithm.

In the traditional model of monostatic synthetic aperture radar (SAR), the flying platform should have a uniform linear trajectory. In practice, the flight path of the SAR platform, which is highly nonlinear or curvy caused by 3-D velocity and acceleration, cannot be used in the traditional model. In this paper, a geometrical model of the monostatic SAR with general configurations is graphically illustrated by vector notation. Moreover, the gradient method is utilized to point out the effects of the motion parameters, namely, velocity vector and acceleration vector, on total bandwidth and image resolution. Based on the accurate model, a general frequency-domain algorithm, with the incorporations of pre- and postprocessing, is proposed to focus the raw data. Applicability is studied through theoretical analysis and numerical experiments. All these general analyses can be applied to different realizations of monostatic SAR mode, including spotlight SAR, sliding spotlight SAR, and Terrain Observation by Progressive Scans (TOPS) SAR.

Synthetic aperture radar (SAR) imaging is usually performed along a straight path. In practice, variations from the ideal caused by maneuvers with acceleration are inevitable. The main problem is the complex signal processing, particularly in the highly squinted spotlight mode. In this paper, acceleration model is analyzed in more details. Impacts are obtained how the acceleration influences the Doppler parameters and space-variant terms, including the SAR resolution and azimuth bandwidth. According to the special signal properties of the acceleration case, an approximation of the range history is made to avoid using the method of series reversion (MSR) to obtain an accurate spectrum. Based on the high-accurate spectrum, a spotlight algorithm with a modified two-step approach is given. Simulation results show the effectiveness of the modified algorithm.

A new wavenumber domain mapping method for the highly squinted beam steering synthetic aperture radar (BS-SAR) is analysed. After the mapping operation, the two dimensional (2-D) spectrums have a broadside form which can be regarded as an equivalent broadside SAR. Furthermore, a novel 2-D two-step approach is introduced to avoid spectral aliasing and skewing caused by the beam steering and the high squint angle. With the mapping operation being incorporated into the novel two-step approach, the baseband azimuth scaling (BAS) algorithm which is only used for broadside cases can be applied for the highly squinted BS-SAR without subaperture.

In geosynchronous (GEO) synthetic aperture radar (SAR), the high orbit height and the long integration time would lead to the significant round-trip delay time and the curved flight path, thus the traditional range model with ‘stop-go’ assumption will be ineffective. In this Paper, based on the analysis of instantaneous Doppler frequency of GEO SAR, an equivalent midpoint mathematical model is proposed to accurately describe the range history, which takes the effect of ‘stop-go’ assumption into account and is more applicable to SAR processing. Based on the equivalent model, the two dimensional (2-D) spectrum of the GEO SAR can be obtained easily by the method of series reversion (MSR). The simulations show the validity of the presented method.

This paper proposes an algorithm to process the data acquired of the targets underneath the circular center, which cannot be focused by frequency algorithms directly. Using the vector expression, the azimuth frequency modulation rate is partitioning into velocity and acceleration parts. After compensation of the acceleration parts, the circular path is corrected to a linear path and the frequency algorithms can be used to focus the data. The simulated results are covered to validate the effectiveness of the proposed algorithm.