Two recent results are combined to create a radar signal with improved performances. The signal is created initially from a coherent train of N identical modified Costas pulses. An orthogonal set of N phase codes is then overlayed on the N pulses.

Costas arrays are permutation matrices that also provide a frequency indexing sequence that permits at most one coincident tone in cross-correlations of FSK waveforms. As such, they have obvious application as frequency indexing sequences in radar and communications when long codes with bounded autocorrelation are required or when Doppler is a significant portion of the transmitted bandwidth. All Costas arrays for orders less than 26 are known, with those for N=24 and N=25 disclosed here. Higher orders are found through number-theoretic generators and partial searches.

In Multistatic Continuous Wave radar the choice of codes and frequencies used for transmission has strong influence on detection and ease of parameter extraction. This paper describes the various effects of using single and multiple codes in a number of separated transmitters, either with the same or separated carrier frequencies. To visualize some of the results, synthetic radar data have been generated and used in the processing.

Pulse compression is essentially an estimation procedure in which the complex amplitude for a given range cell is to be estimated while mitigating the interference from neighboring range cells that results from the convolution of the transmitted waveform with the range swath of interest. Traditionally, matched filtering is employed to estimate the range returns whereby the neighboring range cells are suppressed by a fixed amount that is dictated by the range sidelobes of the matched filter. However, matched filtering is a misnomer in that the receive filter is matched only to the transmitted waveform and not to the actual received signal. This paper extends the previously proposed Reiterative Minimum Mean-Square Error (RMMSE) algorithm for adaptive pulse compression whereby the true matched filter for each individual range cell is estimated based upon the actual received signal resulting in range sidelobes that are adaptively suppressed to the level of the noise floor. The convergence of the RMMSE algorithm is addressed along with the doppler tolerance.