RADAR SIGNAL PROCESSOR, AND RADAR SYSTEM

PROBLEM TO BE SOLVED: To provide a radar signal processor that is configured so as to make it possible to reduce DC offsets with excellent performance.SOLUTION: A radar signal processor comprises an intermediate frequency amplifier 19 that includes a frequency conversion unit 18 subjecting a signal of a radar wave reflected upon a target to a frequency conversion in accordance with a chirp frequency to demodulate the signal having the frequency converted, a variable amplification unit 23 to be connected to a latter step of the frequency conversion unit, and a feedback unit 24 detecting an output of the variable amplification unit, and feeding back a signal of a frequency band to be included in the detection signal to an input of the variable amplification unit. The intermediate frequency amplifier cuts off a frequency band including a DC offset transient response frequency generating when the signal is subjected to the frequency conversion by the frequency conversion unit in a first prescribed period since the frequency conversion unit is used to start the demodulation by the chirp frequency, or/and a specified period setting down a second prescribed period from a demodulation end, and does not cut off the frequency band in a period other than the specified period.SELECTED DRAWING: Figure 2 【課題】ＤＣオフセットを性能良く低減できるようにしたレーダ信号処理器を提供する。【解決手段】レーダ信号処理器は、ターゲットに反射されたレーダ波の信号をチャープ周波数に応じて周波数変換して復調する周波数変換部１８と、周波数変換部の後段に接続される可変増幅部２３と、可変増幅部の出力を検出し当該検出信号に含まれる周波数帯の信号を可変増幅部の入力にフィードバックするフィードバック部２４とを備えた中間周波数増幅器１９を備える。中間周波数増幅器は、周波数変換部を用いてチャープ周波数により復調開始してから第１所定期間、又は／及び、復調終了してから第２所定期間を定めた規定期間において周波数変換部により周波数変換されるときに生じるＤＣオフセット過渡応答周波数を含む周波数帯をカットし規定期間以外の期間には周波数帯をカットしない。【選択図】図２