Title:
RADIO TRANSMITTER, AND ITS TRANSMISSION POWER CONTROL METHOD
Document Type and Number:
Japanese Patent JP3507813
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To provide a radio transmitter having a power detection function to control power that attains power control with a high dynamic range, high accuracy and relieves a software load at high-speed.
SOLUTION: A 1st computer 1 applies averaging to amplitude data of a base band signal. A radio section 2 converts the base band signal into a radio frequency signal to amplify the power corresponding to a power control voltage. A logarithmic amplifier 5 supervises an output power of the wireless section, converts the output power into a voltage corresponding to a logarithm and an analog/digital converter 6 digitizes the voltage. A 2nd computer 7 applies logarithmic averaging calculation to the voltage and a 3rd computer 8 applies linear average calculation through logarithmic value-linear conversion. A comparator 9 recognizes that the fluctuation in power is small when a difference between the calculation result by the 2nd computer and the calculation result by the 1st computer is smaller than a prescribed value and further compares the calculation result by the 3rd computer with the calculation result of the 1st computer and decides a power control voltage of the radio section on the basis of the result of comparison.
Inventors:
Hiroaki Ohba
Application Number:
JP2001159339A
Publication Date:
March 15, 2004
Filing Date:
May 28, 2001
Export Citation:
Assignee:
Saitama NEC Corporation
International Classes:
H03G3/20; H04B1/04; (IPC1-7): H04B1/04; H03G3/20
Domestic Patent References:
| JP61210727A | ||||
| JP61210726A | ||||
| JP61210728A |
Attorney, Agent or Firm:
Masahiko Desk (2 outside)