Abstract: In a spread spectrum receiver, a despread section 102 despreads received signals ELI and ELQ through correlation of spread signals PnI and PnQ. An integration section 103 integrates I-phase correlation data PELI and Q-phase correlation data PELQ. A lead/lag addition section 104 adds, to I-phase integration data PELICc, lead/lag information representing whether the signal output from the integration section is in a lead phase or a lag phase. A delay circuit 108 delays, by one symbol, Q-phase integration data PELQCc and I-phase lead/lag information added integration data PELIa. A lead/lag level difference output section 109 outputs a level difference TAC between lead phase and lag phase. Further, a timing control section 112 controls the phase of the entire loop so as to eliminate the level difference, thus tracking synchronization of the spread signals.

Abstract: A rake receiver is provided with a first decimating unit for extracting received signals in order to perform synchronous acquisition, and a second decimating unit for extracting received signals from a synchronously acquired clock. A despreading unit is used to despread the received signals extracted by the second decimating unit with a PN code and also for supplying the resulting data to a time tracking unit. A second despreading unit is used to despread received signals extracted by the second decimating unit. Selectors are used for switchingly outputting a PN code and the wideband PN code to the second despreading unit. The data to be supplied to the pilot carrier tracking unit and the data path demodulating unit are despread by using the second despreading unit common to those units. The number of despreading units can thus be reduced to two.

Abstract: A radio communication apparatus has a radio wave signal communication circuit and a speed detection circuit for detecting a speed of the radio communication apparatus relative to the base station from an output of the radio wave signal communication circuit. Various operations for security such as neglecting arrival of a call when the vehicle carrying the radio communication apparatus is in a high speed condition are selectively executed in accordance with the detected speed signal. A method of communicating with a base station with various operations mentioned above is also disclosed.