Mobile communication apparatus with an automatic frequency controller
AssigneeNEC Corporation
InventorMariko Matsumoto
Life of this patent
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Abstract
A plurality of finger units despread a received signal with a first spread code to output pilot signals of a receiving channel which has been spread with the first spread code. An AFC unit despreads the received signal with a second spread code to output a pilot signal of an AFC channel which has been spread with the second spread code. An automatic frequency controller calculates a difference between an oscillating frequency of a oscillator and a frequency of the received signal for the channels based on the pilot signals of the receiving and AFC channels to supply a frequency control signal to the oscillator, whereby the oscillating frequency of the oscillator is controlled so that the oscillating frequency is substantially equal to the frequency of the received signal.
Claims30
A mobile communication apparatus, comprising:
- a first signal processor that despreads a received signal with a first spread code to obtain a first pilot signal of a first channel;
- a second signal processor that despreads the received signal with a second spread code to obtain a second pilot signal of a second channel;
- and
- a controller coupled to said first and second signal processors, that controls an operation frequency of the mobile communication apparatus based on the first and second pilot signals, wherein the first and second spread codes are different codes and the first and second pilot signals are different pilot signals.
A communication apparatus, comprising:
- a first despreader that despreads a received signal with a first spread code to obtain a first pilot signal of a first channel, wherein the first channel has been spread with the first spread code;
- a second despreader that despreads the received signal with a second spread code to obtain a second pilot signal of a second channel, wherein the second channel has been spread with the second spread code;
- and
- a controller that calculates a difference between an operation frequency of the communication apparatus and a frequency of the received signal based on the pilot signals of both the first and second channels to control the operation frequency, wherein the first and second spread codes are different codes and the first and second pilot signals are different pilot signals.
A receiver, comprising:
- a radio communication unit having an oscillator, that receives a signal and outputs a received signal;
- a plurality of first despreaders that despread the received signal with a first spread code to output first pilot signals of a first channel which has been spread with the first spread code;
- a second despreader that despreads the received signal with a second spread code to output a second pilot signal of a second channel which has been spread with the second spread code;
- and
- an automatic frequency controller that calculates a difference between an oscillating frequency of the oscillator and a frequency of the received signal for each of the first and second channels based on the first pilot signals and the second pilot signal to supply a frequency control signal to the oscillator, whereby the oscillating frequency of the oscillator is controlled so that the oscillating frequency is substantially equal to the frequency of the received signal.
A method of controlling an operation frequency of a receiver, the method comprising:
- despreading a received signal with a first spread code to obtain a first pilot signal of a first channel which has been spread with the first spread code;
- despreading a received signal with a second spread code to obtain a second pilot signal of a second channel which has been spread with the second spread code;
- calculating a difference between an operation frequency of the receiver and a frequency of the received signal based on the first and second pilot signals;
- and
- controlling the operation frequency based on the difference, wherein the first and second spread codes are different codes and the first and second pilot signals are different pilot signals.
Dependencies are inferred from the claim text.