| 摘要 |
PURPOSE: A preamble receiver for a CDMA(Code Division Multiple Access) system is provided to use the entire memory of a hardware by adjusting the number of signatures capable of reception, according to a cell radius. CONSTITUTION: Double buffers(20,30) store 16 one-time and half-time data per a chipx1 clock. Multiplexers(51-58) alternately select the one-time and half-time data stored in the double buffers(20,30) per chipx8 clocks. Code double buffers(70,80) store 15 preamble codes per the chipx1 clock. A 16-bit shift register(90) and an 128-bit shift register(100) shift data stored in the code double buffers(70,80) by one bit per chipx4 clocks. Multipliers(111-118) multiply data outputted from the multiplexers(51-58) by data outputted from the 16-bit shift register(90) according to each bit. Adders(121-128,131-134,141,142,150) add bits of data outputted from multipliers(111-118). An 16-bit adder(160) adds data outputted from the adders(121-128,131-134,141,142,150) and data stored in a memory(170) per the chipx8 clocks, and record the added data in the memory(170). |
