Bistatic SAR system with GPS transmitter

A Novel Range Compression Algorithm for The~Resolution Enhancement in GNSS-SAR

“…Because the terms A r and exp (jφ r (u)) are constants with respect to t, the duration of (4) will be determined by the term Λ (•). Thus the attainable range resolution with respect to pulse duration can be expressed as [1][2][3][4][6][7][8][9][10][11]14,17]…”

“…With the conventional GNSS-SAR imaging algorithm which includes both range and azimuth compression, range resolution is determined by signals bandwidth and bi-static angle for sensing while azimuth resolution is determined by Doppler frequency shift [1][2][3][4][5][6][7][8][9][10][11][12]14,15,17]. But in a numbers of typical literature such as [1][2][3][4][5][6][7][8][9][10][11][12]14,15,17], the system is considered as quasi-monostatic case, which means the bi-static angle can be regarded as zero. Thus the range resolution is merely determined by signal bandwidth among these works.…”

“…Concerning the value of range resolution, it is proportional to the reciprocal of doubled signal bandwidth value, and for GNSS signals, the bandwidth value is equal to the Pseudo-Random Noise (PRN) code chip rate [1,2]. Because the chip rate of GPS C/A code, P code and GLONASS P code are 1.023MHz, 10.023MHz, and 5.11MHz respectively, the range resolutions can be obtained at the levels 150 m, 15 m and 30 m, respectively; for full band Galileo E5 signal, the PRN code chip rate is 51.150MHz, thus the range resolution is achieved at 3 meters level [1][2][3][4][5][6][7][8][9][10][11][12]14,15,17]. Looking at the azimuth resolution of GNSS-SAR, the level less than 1 meter can be achieved [1,2].…”

A Novel Range Compression Algorithm for Resolution Enhancement in GNSS-SARs

“…With a conventional GNSS-SAR imaging algorithm that includes both range and azimuth compression, range resolution is determined by GNSS signal bandwidth and bi-static angle for sensing, while azimuth resolution is determined by Doppler frequency shift [ 1 , 2 , 4 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 ]. However, when the system is considered as a quasi-monostatic case, in which the bi-static angle is and range and azimuth domain are orthogonal, range resolution is mainly decided by the GNSS signal bandwidth [ 1 , 2 , 4 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 ]. If shape factors of a wave form are not considered, potential range resolution identically equals the reciprocal of doubled signal bandwidth value.…”

“…For instance, because the chip rate of GPS Coarse Acquisition Code (C/A) code signal is MHz, the potential range resolution is obtained at the level of 150 m [ 1 , 2 , 16 ]. A GLONASS P code signal, where the chip rate is MHz, with GPS P code signal and Beidou signal, where the chip rate is MHz, were used in works [ 1 , 2 , 4 , 6 , 7 , 8 , 9 , 10 , 12 , 13 , 17 ], respectively. The potential range resolution for [ 1 , 2 , 10 , 12 , 13 ] was obtained at the level of 30 m and 15 m in [ 4 , 6 , 7 , 8 , 9 , 17 ].…”