__init__.py 文件源码

def estimate_range(tx,rx,fs,quiet=False):
    """
    tx: the known, noise-free, undelayed transmit signal (bistatic radars agree beforehand on the psuedorandom sequence)
    rx: the noisy, corrupted, interference, jammed signal to estimate distance from
    fs: baseband sample frequency
    """
    Rxy =  np.correlate(tx, rx, 'full')
    lags = np.arange(Rxy.size) - Rxy.size // 2
    pklag = lags[Rxy.argmax()]

    distest_m = -pklag / fs / 2 * c

    mR = abs(Rxy)  # magnitude of complex cross-correlation
    if not quiet and figure is not None:
        ax = figure().gca()
        ax.plot(lags,mR)
        ax.plot(pklag,mR[mR.argmax()], color='red', marker='*')
        ax.set_title('cross-correlation of receive waveform with transmit waveform')
        ax.set_ylabel('$|R_{xy}|$')
        ax.set_xlabel('lags')
        ax.set_xlim(pklag-100,pklag+100)


    return distest_m