摘要 |
<p>A novel and improved method and apparatus for searching is described. Channel data is despread utilizing a matched filter structure. The in-phase and quadrature amplitudes of the despreading (410) delivered to coherent accumulators (430, 432) to sum for a programmable duration of time. The amplitude accumulations are squared and summed (440) to produce an energy measurement. The energy measurement is accumulated for a second programmable time to perform non-coherent accumulation (450). The resulting value is used to determine the likelihood of a pilot signal at that offset. Each matched filter structure comprises an N-value shift register for receiving data, a programmable bank of taps to perform despreading and optional Walsh decovering, and an adder structure to sum the resulting filter tap calculations.</p> |