Accession Number : AD1045936


Title :   A high powered radar interference mitigation technique for communications signal recovery with fpga implementation


Descriptive Note : Technical Report,01 Mar 2017,01 Mar 2017


Corporate Author : Naval Postgraduate School Monterey United States


Personal Author(s) : Meager,Geoffrey R


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/1045936.pdf


Report Date : 01 Mar 2017


Pagination or Media Count : 69


Abstract : In this thesis, we investigate the demodulation of a communications signal that is interfered with by a high-powered radar signal. We choose quaternary phase-shift keying (QPSK) modulation for illustration. The radar phase offset is initially assumed to be fixed. Later, a practical phase sequence is added to the phase offset. A least-squares estimator (LSE) is used to estimate the amplitude and fixed-phase offset of the interfering radar signal to be used for interference cancellation. Then, we utilize a maximum-likelihood detection (MLD) receiver. We show that the QPSK symbol error ratio (SER) improvement in the radar interference depends on collection time. The variance of the estimate increases as the QPSK signal-to-noise ratio (SNR) increases. The increase in variance affects SER. SER results approach the ideal with increasing collection times. For the case where the phase offset includes a phase sequence, the original LSE technique is modified. Later, a system is created in Simulink and converted to hardware-description language (HDL). The SER performance of the HDL implementation in hardware is compared to those of the signal model. SER performance is somewhat degraded in the hardware implementation.


Descriptors :   radar , RADAR INTERFERENCE , ELECTRONIC WARFARE , RADAR RECEIVERS


Subject Categories : Active & Passive Radar Detection & Equipment


Distribution Statement : APPROVED FOR PUBLIC RELEASE