Portable type radio equipment

Abstract

In a radio equipment of portable type, the impedance of an antenna is optimized by adjusting a matching circuit which has the adjustment function and is connected to an antenna, based on a reflection phase sent back from the antenna, outputted from a reflection phase detector, and a current supplied to a transmitter-receiver which generates a transmitting signal.

1 - 24 . (canceled)  
   
   
       25 . A method of adjusting a variable impedance in an impedance matching circuit connected to an antenna having an antenna impedance, the antenna being included in a radio communication equipment, said method comprising: 
 supplying an electric power to a transmitting circuit to generate a transmitting signal;    detecting the electric power supplied to the transmitting-circuit;    generating a power detecting signal;    generating an antenna reflection signal having a certain phase depending on the transmitting signal supplied to the antenna;    adjusting the variable impedance to match the antenna with the transmitting circuit;    detecting the phase of the antenna reflection signal from the antenna to generate a phase detection signal at a phase detection circuit;    selecting one of the phase detection circuit and the transmitting circuit to the antenna;    controlling the selecting circuit to receive the phase detection signal and the power detection signal at a control circuit; and    controlling the impedance matching circuit to set the variable impedance depending on the phase detection signal and the power detection signal at the control circuit.    
   
   
       26 . The method according to  claim 25 , further comprising: 
 generating first and second selection signals at the control circuit;    supplying one of the first and second selection signals to the selecting circuit, the selecting circuit connecting the antenna to the phase detection circuit in response to the first selecting signal, and connecting the antenna to the transmitting circuit in response to the second signal.    
   
   
       27 . The method according to  claim 25 , wherein said controlling includes: 
 storing a reference phase signal and a reference power signal in the control circuit; and    adjusting the impedance of the impedance matching circuit in accordance with the comparison between the phase detection signal and the reference phase signal, and between the power detection signal and the reference power signal.    
   
   
       28 . The method according to  claim 27 , wherein said controlling further includes: 
 determining a method of adjusting the impedance matching circuit depending on the comparison between the phase detection signal and the reference phase signal; and    comparing the power detection signal with the reference power signal to set the variable impedance in the impedance matching circuit.    
   
   
       29 . The radio communication equipment according to  claim 28 , wherein the adjustment method corresponds to one of increasing and decreasing the variable impedance.