Code division multiple access mobile communication system

Claim 2

A code division multiple access mobile communication system for spreading, modulating and transmitting a pilot signal along with data into radio frequency band signals, demodulating and despreading the received radio frequency band signals into a received pilot signal and received data, and generating a phase correction signal from the received pilot signal so that a phase error of the received data is corrected by use of said phase correction signal during detection, the system comprising: a plurality of mobile stations and a base station, said base station establishing up and down links in conjunction with said plurality of mobile stations; each of said plurality of mobile stations having a detection circuit including: a voltage-controlled oscillator for supplying a carrier to a radio frequency quadrature demodulator demodulating the received radio frequency band signals; an averaging circuit for averaging a first step phase correction signal generated from the received pilot signal and outputting said phase correction signal; and a frequency controller for detecting a frequency error from said first step phase correction signal, said frequency controller further generating from said frequency error a control signal to control the frequency of the carrier generated by said voltage-controlled oscillator, wherein said frequency controller comprises: a phase change generating circuit for generating a phase change based on said frequency error derived from said first step phase correction signal and a signal preceding said first step phase correction signal by a predetermined delay time; and an integrating circuit for integrating said phase change and outputting the integrated result as said control signal.

Claim 3

A code division multiple access mobile communication system according to claim 1, wherein said predetermined delay time is set within a range not exceeding the delay time needed for averaging by said averaging circuit.

Claim 4

A code division multiple access mobile communication system according to claim 2, wherein said plurality of mobile stations each include a radio frequency quadrature modulator supplied with the carrier from said voltage-controlled oscillator.

Claim 5

A code division multiple access mobile communication system according to claim 3, wherein said plurality of mobile stations each set a spreading ratio variably in keeping with changing bit rates of data and generate a spread signal for transmission having a constant chip rate.

Claim 6

A code division multiple access mobile communication system for transmitting and receiving data spread by a spread code over a radio frequency band, the system comprising: a plurality of mobile stations and a base station; said plurality of mobile stations each having a detection circuit including: a temporary judge circuit acting when each of a sign of a cosine component and a sign of a sine component of despread data is found to be inverted one symbol later, said temporary judge circuit thereupon inverting the signs of the components individually and outputting the sign-inverted components, said temporary judge circuit further outputting the components uninverted when the signs thereof are found to be uninverted one symbol later; a frequency controller for generating a phase change based on the frequency error derived from the output signal of said temporary judge circuit and from a signal preceding said output signal by a predetermined delay time, said frequency controller further integrating said phase change and outputting the integrated result as a control signal; a voltage-controlled oscillator for receiving said control signal as a signal to control an oscillation frequency; and a radio frequency quadrature demodulator for receiving the output signal of said voltage-controlled oscillator as a carrier to demodulate received radio frequency band signals; wherein said base station establishes up and down links in conjunction with said plurality of mobile stations.

Claim 7

A code division multiple access mobile communication system for transmitting and receiving data spread by a spread code over a radio frequency band, the system comprising: a plurality of mobile stations and a base station; said plurality of mobile stations each having a detection circuit including: a temporary judge circuit acting when each of a sign of a cosine component and a sign of a sine component of despread data is found to be inverted one symbol later, said temporary judge circuit thereupon inverting the signs of the components individually and outputting the sign-inverted components, said temporary judge circuit further outputting the components uninverted when the signs thereof are found to be uninverted one symbol later; a frequency controller for generating a phase change based on the frequency error derived from the output signal of said temporary judge circuit and from a signal preceding said output signal by a predetermined delay time, said frequency controller further integrating said phase change and outputting the integrated result as a control signal; a voltage-controlled oscillator for receiving said control signal as a signal to control an oscillation frequency; and a radio frequency quadrature demodulator for receiving the output signal of said voltage-controlled oscillator as a carrier to demodulate received radio frequency band signals; wherein said base station establishes up and down links in conjunction with said plurality of mobile stations.

Claim 8

A mobile station for use with a code division multiple access mobile communication system for spreading, modulating and transmitting a pilot signal along with data into radio frequency band signals, demodulating and despreading the received radio frequency band signals into a received pilot signal and received data and generating a phase correction signal from the received pilot signal so that a phase error of the received data is corrected by use of said phase correction signal from the received pilot signal so that a phase error of the received data is corrected by use of said phase correction signal during detection, said mobile station having a detection circuit comprising: a voltage-controlled oscillator for supplying a carrier to a radio frequency quadrature demodulator demodulating the received radio frequency band signals; an averaging circuit for averaging a first step phase correction signal generated from the received pilot signal and outputting said phase correction signal; and a frequency controller for detecting a frequency error from said first step phase correction signal, said frequency controller further generating from said frequency error a control signal to control the frequency of said voltage-controlled oscillator, wherein said frequency controller comprises: a phase change generating circuit for generating a phase change based on said frequency error derived from said first step phase correction signal and from a signal preceding said first step phase correction signal by a predetermined delay time; and an integrating circuit for integrating said phase change and outputting the integrated result as said control signal.

Claim 9

A mobile station for use with a code division multiple access mobile communication system for spreading, modulating and transmitting a pilot signal along with data into radio frequency band signals, demodulating and despreading the received radio frequency band signals into a received pilot signal and received data and generating a phase correction signal from the received pilot signal so that a phase error of the received data is corrected by use of said phase correction signal from the received pilot signal so that a phase error of the received data is corrected by use of said phase correction signal during detection, said mobile station having a detection circuit comprising: a voltage-controlled oscillator for supplying a carrier to a radio frequency quadrature demodulator demodulating the received radio frequency band signals; an averaging circuit for averaging a first step phase correction signal generated from the received pilot signal and outputting said phase correction signal; and a frequency controller for detecting a frequency error from said first step phase correction signal, said frequency controller further generating from said frequency error a control signal to control the frequency of said voltage-controlled oscillator, wherein said frequency controller comprises: a phase change generating circuit for generating a phase change based on said frequency error derived from said first step phase correction signal and from a signal preceding said first step phase correction signal by a predetermined delay time; and an integrating circuit for integrating said phase change and outputting the integrated result as said control signal.

Claim 10

A mobile station according to claim 6, wherein said predetermined delay time is set within a range not exceeding the delay time needed for averaging by said averaging circuit.

Claim 11

A mobile station according to claim 7, further comprising a radio frequency quadrature modulator supplied with the carrier from said voltage-controlled oscillator.

Claim 12

A mobile station according to claim 8, further comprising means for setting a spreading ratio variably in keeping with changing bit rates of data and for generating a spread signal for transmission having a constant chip rate.

Claim 13

A mobile station for use with a code division multiple access mobile communication system for transmitting and receiving data spread by a spread code over a radio frequency band, said mobile station having a detection circuit comprising: a temporary judge circuit acting when each of a sign of a cosine component and a sign of a sine component of despread data is found to be inverted one symbol later, said temporary judge circuit thereupon inverting the signs of the components individually and outputting the sign-inverted components, said temporary judge circuit further outputting the components uninverted when the signs thereof are found to be uninverted one symbol later; a frequency controller for generating a phase change based on the frequency error derived from the output signal of said temporary judge circuit and from a signal preceding said output signal by a predetermined delay time, said frequency controller further integrating said phase change and outputting the integrated result as a control signal; a voltage-controlled oscillator for receiving said control signal as a signal to control an oscillation frequency; and a radio frequency quadrature demodulator for receiving the output signal of said voltage-controlled oscillator as a carrier to demodulate received radio frequency band signals.

Claim 14

A mobile station for use with a code division multiple access mobile communication system for transmitting and receiving data spread by a spread code over a radio frequency band, said mobile station having a detection circuit comprising: a temporary judge circuit acting when each of a sign of a cosine component and a sign of a sine component of despread data is found to be inverted one symbol later, said temporary judge circuit thereupon inverting the signs of the components individually and outputting the sign-inverted components, said temporary judge circuit further outputting the components uninverted when the signs thereof are found to be uninverted one symbol later; a frequency controller for generating a phase change based on the frequency error derived from the output signal of said temporary judge circuit and from a signal preceding said output signal by a predetermined delay time, said frequency controller further integrating said phase change and outputting the integrated result as a control signal; a voltage-controlled oscillator for receiving said control signal as a signal to control an oscillation frequency; and a radio frequency quadrature demodulator for receiving the output signal of said voltage-controlled oscillator as a carrier to demodulate received radio frequency band signals.

Claim 15

A code division multiple access mobile communication system for spreading, modulating and transmitting a pilot signal along with data into radio frequency band signals, demodulating and despreading the received radio frequency band signals into a received pilot signal and received data and generating a phase correction signal from the received pilot signal so that a phase error of the received data is corrected by use of said phase correction signal from the received pilot signal so that a phase error of the received data is corrected by use of said phase correction signal during detection, the system comprising: a plurality of mobile stations and a base station, said base station establishing up and down links in conjunction with said plurality of mobile stations; each of said plurality of mobile stations having a detection circuit including: a voltage-controlled oscillator for supplying a carrier to a radio frequency quadrature demodulator demodulating the received radio frequency band signals; an averaging circuit for averaging a first step phase correction signal generated from the received pilot signal and outputting said phase correction signal; and means for detecting a frequency error from said first step phase correction signal, and for generating from said frequency error a control signal to control the frequency of the carrier generated by said voltage-controlled oscillator, wherein said means for detecting comprises: means for generating a phase change based on said frequency error derived from said first step phase correction signal and from a signal preceding said first step phase correction signal by a predetermined delay time; and means for integrating said phase change and outputting the integrated result as said control signal.

Claim 16

A code division multiple access mobile communication system for spreading, modulating and transmitting a pilot signal along with data into radio frequency band signals, demodulating and despreading the received radio frequency band signals into a received pilot signal and received data and generating a phase correction signal from the received pilot signal so that a phase error of the received data is corrected by use of said phase correction signal from the received pilot signal so that a phase error of the received data is corrected by use of said phase correction signal during detection, the system comprising: a plurality of mobile stations and a base station, said base station establishing up and down links in conjunction with said plurality of mobile stations; each of said plurality of mobile stations having a detection circuit including: a voltage-controlled oscillator for supplying a carrier to a radio frequency quadrature demodulator demodulating the received radio frequency band signals; an averaging circuit for averaging a first step phase correction signal generated from the received pilot signal and outputting said phase correction signal; and means for detecting a frequency error from said first step phase correction signal, and for generating from said frequency error a control signal to control the frequency of the carrier generated by said voltage-controlled oscillator, wherein said means for detecting comprises: means for generating a phase change based on said frequency error derived from said first step phase correction signal and from a signal preceding said first step phase correction signal by a predetermined delay time; and means for integrating said phase change and outputting the integrated result as said control signal.

Claim 17

A mobile station for use with a code division multiple access mobile communication system for spreading, modulating and transmitting a pilot signal along with data into radio frequency band signals, demodulating and despreading the received radio frequency band signals into a received pilot signal and received data and generating a phase correction signal from the received pilot signal so that a phase error of the received data is corrected by use of said phase correction signal during detection, said mobile station having a detection circuit comprising: a voltage-controlled oscillator for supplying a carrier to a radio frequency quadrature demodulator demodulating the received radio frequency band signals; an averaging circuit for averaging a first step phase correction signal generated from the received pilot signal and outputting said phase correction signal; and means for detecting a frequency error from said first step phase correction signal, and for generating from said frequency error a control signal to control the frequency of said voltage-controlled oscillator, wherein said means for detecting comprises: means for generating a phase change based on said frequency error derived from said first step phase correction signal and from a signal preceding said first step phase correction signal by a predetermined delay time; and means for integrating said phase change and outputting the integrated result as said control signal.

Claim 18

A mobile station for use with a code division multiple access mobile communication system for spreading, modulating and transmitting a pilot signal along with data into radio frequency band signals, demodulating and despreading the received radio frequency band signals into a received pilot signal and received data and generating a phase correction signal from the received pilot signal so that a phase error of the received data is corrected by use of said phase correction signal during detection, said mobile station having a detection circuit comprising: a voltage-controlled oscillator for supplying a carrier to a radio frequency quadrature demodulator demodulating the received radio frequency band signals; an averaging circuit for averaging a first step phase correction signal generated from the received pilot signal and outputting said phase correction signal; and means for detecting a frequency error from said first step phase correction signal, and for generating from said frequency error a control signal to control the frequency of said voltage-controlled oscillator, wherein said means for detecting comprises: means for generating a phase change based on said frequency error derived from said first step phase correction signal and from a signal preceding said first step phase correction signal by a predetermined delay time; and means for integrating said phase change and outputting the integrated result as said control signal.