Adaptive Interference Cancellation Method Research Articles

A new adaptive co-site broadband interference cancellation method with auxiliary channel

With the boom of the communication systems on some independent platforms (such as satellites, space stations, airplanes, and vessels), co-site interference is becoming prominent. The adaptive interference cancellation method has been adopted to solve the co-site interference problem. But the broadband interference cancellation performance of traditional Adaptive Co-site Interference Cancellation System (ACICS) with large delay mismatching and antenna sway is relatively poor. This study put forward an Adaptive Co-site Broadband Interference Cancellation System With Two Auxiliary Channels (ACBICS-2A). The system model was established, and the steady state weights and Interference Cancellation Ratio (ICR) were deduced by solving a time-varying differential equation. The relationship of ICR, system gain, modulation factor, interference signal bandwidth and delay mismatching degree was acquired through an in-depth analysis. Compared with traditional adaptive interference cancellation system, the proposed ACBICS-2A can improve broadband interference cancellation ability remarkably with large delay mismatching and antenna sway for the effect of auxiliary channel. The maximum improved ICR is more than 25 ​dB. Finally, the theoretical and simulation results were verified by experiments.

무선 중계 시스템에서의 적응 간섭 제거 방식

이동통신서비스가 넓게 확대되고, 서비스영역의 확대로 인해 중계기가 급속히 증가하고 있다. 이동통신 서비스의 큰 서비스 구역으로 간섭제거시스템을 위한 새로운 Signed CMA알고리즘을 제안한다. 제안된 Signed CMA알고리즘은 조정된 스텝사이즈 값에 의해 성능이 개선된다. 우리는 Signed CMA의 평균자승에러를 개선한다. 매트랩은 실험결과에 맞춰 제안된 알고리즘과 비교 분석하여 사용한다. 수렴횟수 1000번일 때 스텝사이즈 0.0065를 가진 제안된 Signed CMA알고리즘의 최소자승에러 성능이 기존 CMA 알고리즘보다 약 5 dB 더 낫다.

A New Wide-Band System Architecture for Mobile High Frequency Communication Networks

A new wide-band HF communication system architecture for a multiple, mobile terminal network has been proposed and analyzed. This architecture embodies the complete removal of high power switching and tuning and achieves control of unwanted radiation by the use of highly linear power amplifiers and adaptive interference cancellation methods. To provide maximum flexibility in system operation, provision is made for transmitting and receiving subsystem assets to be shared among users to the greatest degree possible. The transmitter is simply a power bank into which all exciters are connected, and each receiver has access to a selection of antennas through power dividers, diversity combiners, and adaptive array processors. The implementation of this architecture will permit rapid and flexibile frequency selection and channel configuration to accommodate the complex network relaying strategy that will be necessary in modern warfare environment. Research is being conducted by the U.S. Navy on the technologies that require advancement if this architecture is to be brought to fruition for intratask-force communication. A system engineering analysis, substantial measurements and simulations of adaptive cancellation system performance, and development of critical system components have been conducted to validate the architectural concept.