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本文讨论了天波后向散射型超视距雷达的地物特性及目标特性。由于超视距雷达波束对地的入射余角大,波束照射地面的面积大,它的地物回波强度也就相当大。文内列举了用某雷达测得的地物后向散射系数值及地物回波经电离层反射后多卜勒漂移值。在工作频率为1O.4~16.25兆赫时,测得祁连山区后向散射系数为-10.5~24.1分贝;沙漠地区后向散射系数为-17.8~-30分贝。冬季电离层较稳定时,地物回波多卜勒漂移值小于±5赫的范围(-60分贝点),夏季多卜勒漂移值就更大,如82年7月8日测得地
This article discusses the sky wave backscatter type of over-the-horizon radar features and target characteristics. Due to the large incident angle of the beam from the over-the-horizon radar to the ground and the large area of the ground irradiated by the beam, the intensity of its echoes is quite large. The paper lists the backscattering coefficient measured by a radar and the Doppler shift value of the echoes reflected by the ionosphere. At working frequency of 1O.4 ~ 16.25 MHz, the backscattering coefficient of the Qilian Mountains was measured as -10.5 ~ 24.1 dB; the backscattering coefficient in the desert area was -17.8 ~ -30 dB. In winter, when the ionosphere is stable, the Doppler shift of the object echo is less than ± 5 Hz (-60 dB point), and the summer Doppler shift is even larger, as measured on July 8, 1982