CAJ | 학술논문

同频干扰(收发天线的直接耦合波，表面直接发射波)由于其具有很强的能量对近场瞬态主动电磁探测系统的目标信号造成了严重的干扰，此干扰与目标回波信号同频且强度往往高于目标回波信号，因此，对探测系统的正常工作危害极大。本文分析了传统的同频干扰消除方法，阐述了自适应RLS(递归最小二乘法)滤波的原理，在此基础上提出了一种基于QRD-LS算法的同频干扰消除方法。该方法收敛速度快、运算量较小、能实现实时的信号处理。计算机仿真结果表明该方法可有效抑制同频干扰，提高了目标回波的信干比(SIR)。同时该方法对同频干扰的局部畸变以及幅度、时延的变化具有很强的适用性。
동빈간우(수발천선적직접우합파，표면직접발사파)유우기구유흔강적능량대근장순태주동전자탐측계통적목표신호조성료엄중적간우，차간우여목표회파신호동빈차강도왕왕고우목표회파신호，인차，대탐측계통적정상공작위해겁대。본문분석료전통적동빈간우소제방법，천술료자괄응RLS(체귀최소이승법)려파적원리，재차기출상제출료일충기우QRD-LS산법적동빈간우소제방법。해방법수렴속도쾌、운산량교소、능실현실시적신호처리。계산궤방진결과표명해방법가유효억제동빈간우，제고료목표회파적신간비(SIR)。동시해방법대동빈간우적국부기변이급폭도、시연적변화구유흔강적괄용성。
The same frequency interference (including direct coupling wave of receiving and transmitting antennas, direct surface reflection wave), because of its strong energy, has great effect on the target signal of a near field transient active electromagnetic detection system. This interference has the same frequency as target signal,and is generally bigger than the target signal. Therefore, it is great harm to the detection system’s normal operation.In this paper, the traditional methods of same frequency interference elimination are analyzed,and the working principle of adaptive RLS(recursive least square) filter is presented, then a new method of same frequency interference suppression which is based on recursive QRD-LS algorithm is put forward. The method has fast convergence speed, low operation amount and can realize real-time processing. The simulation results show that this method can effectively suppress the same frequency interference, and improve the SIR(signal to interference radio) of the target signal. Moreover, the method has a good applicability for the local aberration of the same frequency interference and the changes of its amplitude and time-delay.