A novel non-coherent radar pulse compression technique based on periodic m-sequences

Stepped Frequency Pulse Compression With Noncoherent Radar Using Deep Learning

“…The problem is then shifted from a phase retrieval problem to that of finding the inverse of the autocorrelation function. Tests were run where this was used as input data instead, using the normalization in (28) and (29), and applying the IDFT transform before converting to log scale, with the motivation that this might be an easier problem for the DNN. The loss, shown in Table IV, was similar to that of having no DFT on X, i.e.…”

“…9 we have compared the DNN solution to an alternative form of non-coherent pulse compression using OOK. We have compared it to a waveform using m-sequence coding of sub-pulses, see [29], with the same instantaneous bandwidth as the DNN solution. The length of such an msequence is 2 m − 1 which gives 63 sub-pulses for m = 6.…”

“…The length of such an msequence is 2 m − 1 which gives 63 sub-pulses for m = 6. After Manchester coding, [29], the total length of the pulse sequence is 126 sub-pulses with 63 "on" pulses, i.e. it uses approximately the same number of pulses as the presented DNN solution but transmitted within one PRI instead of 64 with a single "sub-pulse" in each.…”

Sequences with Perfect Periodic Auto and Cross Correlation Properties

“…The PACF clearly show that the magnitude of sidelobes other than peak is '1' which is constant. Levanon [13] and Jahangir [14] demonstrated the ideal periodic correlation properties of M-sequences and Legendre sequences by taking the crosscorrelation between the unipolar version {1, 0} of transmitted signal and the bipolar reference signal {±1}. It is shown that this method is advantageous in context of Non-coherent Pulse Compression (NCPC) radar.…”

“…The perfect periodic cross-correlation property is achieved at the cost of high energy loss. The energy efficiency of unipolar M-sequence (N=7) is nearly 57% and such signals are preferred in noncoherent processing [13,14]. For coherent processing, the reference signal must be same as the transmitted signal.…”