A FH(frequency hopping) signal acquisition technology based on frequency estimation was introduced. An adaptive spectral-estimation model was established, and the frequency estimation was implemented by autoregressive and adaptive algorithm. However, for a fading and AWGN (additive-white Gaussian noise) channel, frequency estimation errors might occur. To achieve more accurate and robust acquisition, a new acquisition logic was developed, which would prevent the acquisition scheme from making a wrong decision and leading to the false tracking. The acquisition scheme using multiple antennas was also addressed to combat the fading effect. Numerical results for the probability of the MSB (most significant bit) error and the corresponding mean acquisition time were illustrated for the performance evaluation under unfading and Rayleigh-fading channel conditions. Simulation results indicate that the FH signal frequency can be precisely estimated, and quick acquisition for the frequency-hopping signal is implemented.
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