摘要
电离层探测系统采用线性调频脉冲信号,信号在传输过程中其频谱会受到电离层污染和射频干扰影响,导致距离旁瓣增大和噪声基底抬高,影响回波检测。推导了考虑电离层传输函数的频谱校正表达式,对回波谱进行频谱较正后采用加权技术,与单独采用加权技术主旁瓣抑制比可提高10 dB左右,信干比可提高9 dB左右,同时主瓣扩展系数和信噪比损失与单独采用加权技术相同,大大提高了主旁瓣抑制比和抗干扰能力,提高了回波检测能力。
Linear frequency modulated Pulse signals are used in the ionosphere detecting system, but the spectrum of the signals may be contaminated by the ionosphere and the radio frequency（RF） interference during the transmission. In consequence, the distance sidelobe and the noise will be increased, so the echo detecting will be influenced. In this paper, a modifying spectrum expression is deduced considering the ionosphere transfer-function to amend the echo spectrum, and then a weighted method is adopted. Compared with the former method which merely a weighted method, the ratio of main-lobe to side-lobe is risen by about 10 dB, SNR is risen by about 9 dB, and meanwhile the main-lobe expanding coefficient and SNR loss are the same as the former. In this way, the ratio of main-lobe to sideqobe is largely raised, the capability of anti-jamming and echo detection are improved.
出处
《电波科学学报》
EI
CSCD
北大核心
2008年第6期1085-1089,共5页
Chinese Journal of Radio Science
基金
国家级重点实验室基金项目(K0704Z03)
关键词
线性调频脉冲
斜向探测
旁瓣抑制
射频干扰
频谱校正
linear frequency modulated pulse
oblique detecting
side-lobe suppression
radio frequency（RF） interference
spectrum modifying
