| 摘要 |
PURPOSE:To shorten the mean value of the search time of all phases by independently operating two synchronous detection systems which search the phases of spread codes while the phases are respectively shifted in opposite directions. CONSTITUTION:When a phases of the spread codes generated in a code generator 11a and the spread codes of reception signals are decided that they do not agree in a synchronous detection circuit 6, a synchronous controller 7 shifts the phases of the codes to a positive directions by a 1/2 chip by a +1/2 chip phase shifter 9. When the phases of the diffusion codes generated in the code generator 11b and those of the spread codes of the reception signals are decided that they do not agree, the synchronous controller 7 shifts the phase of the spread codes generated in the second code generator 11b to a negative direction by the 1/2 chip by a -1/2 chip phase shifter 10. Thus, two synchronous detection systems can independently be operated even if there is fluctuation in the time required for respective synchronous decision, and the different synchronous phases can continuously be checked, whereby the mean time for searching all the phases can be shortened. |
