| 摘要 |
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 delivered to coherent accumulators to sum for a programmable duration of time. The amplitude accumulations are squared and summed to produce an energy measurement. The energy measurement is accumulated for a second programmable time to perform non-coherent accumulation. 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. |
