| 摘要 |
PURPOSE: A digital filter device in a mobile communication system is provided to make one terminal process voice channels and fast data channels as well in an IMT-2000(International Mobile Telecommunications-2000) system, and to adopt a memory structure when an FIR(Finite Impulse Response) filter is constituted. CONSTITUTION: A Q(Quadrature) spread code generator(223) receives a long PN(Pseudo Noise) code, a PN code of a short I(In-phase) channel, and a PN code of a short Q channel, and generates PN codes for an I channel and a Q channel for spreading. The first multiplier(201) multiplies inputted data by the PN code of the I channel of the Q spread code generator(223). The second multiplier(203) multiplies the inputted data by the PN code of the Q channel. The first selector(225) alternately outputs output signals of the first and the second multiplier(201,203). The first and the second baseband filter(233,235) filter output signals of the first selector(225). PCH(Paging Channel) multipliers(241,243) multiply gains of data channels outputted from the first and the second baseband filter(233,235). The first and the second baseband filter(233,235) are FIR(Finite Impulse Response) filters. |
