Methods and apparatuses for adaptively controlling antenna parameters to enhance efficiency and maintain antenna size compactness

Abstract

A communications apparatus. The apparatus comprises a transmitting antenna, a receiving antenna, a first serial configuration of a first power amplifier and a first matching network for producing a first signal, the first power amplifier operating in a first frequency band, a second serial configuration of a second power amplifier and a second matching network for producing a second signal, the second power amplifier operating in a second frequency band, a first switching element for switchably supplying the first signal or the second signal to the transmitting antenna, a first and a second receiver; and a second switching element for switchably directing a signal received at the receiving antenna to the first receiver or the second receiver.

What is claimed is: 
     
         1 . A communications apparatus comprising:
 a transmitting antenna;   a receiving antenna;   a first serial configuration of a first power amplifier and a first matching network for producing a first signal, the first power amplifier operating in a first frequency band;   a second serial configuration of a second power amplifier and a second matching network for producing a second signal the second power amplifier operating in a second frequency band;   a first switching element for switchably supplying the first signal or the second signal to the transmitting antenna;   a first receiver;   a second receiver; and   a second switching element for switchably directing a signal received at the receiving antenna to the first receiver or the second receiver.   
     
     
         2 . The communications apparatus of  claim 1  further comprising an isolation structure intermediate the transmitting antenna and the receiving antenna. 
     
     
         3 . The communications apparatus of  claim 2  wherein the isolation structure further comprises a conductive structure disposed between the transmitting antenna and the receiving antenna. 
     
     
         4 . The communications apparatus of  claim 1  further comprising a dielectric substrate, wherein the transmitting and the receiving antennas each comprise a conductive structure disposed on the dielectric substrate and the isolation structure comprises a conductive structure disposed between the transmitting and the receiving antennas. 
     
     
         5 . The communications apparatus of  claim 1  wherein a signal polarization of the transmitting antenna is different from a signal polarization of the receiving antenna. 
     
     
         6 . The communications apparatus of  claim 1  wherein the first matching network presents a load impedance to the first power amplifier responsive to a power-related parameter of the first power amplifier and the second matching network presents a load impedance to the second power amplifier responsive to a power-related parameter of the second power amplifier. 
     
     
         7 . The communications apparatus of  claim 6  wherein the power-related parameter of the first power amplifier or the power-related parameter of the second power amplifier comprises a power amplifier output power, an operating frequency of the communications device or a voltage standing wave ratio on a conductive path between the power amplifier and the transmitting antenna. 
     
     
         8 . The communications apparatus of  claim 6  wherein the load impedance presented by the first matching network to the first power amplifier for controlling an efficiency or a power added efficiency of the first power amplifier signal and the load impedance presented by the second matching network to the second power amplifier for controlling an efficiency or a power added efficiency of the second power amplifier. 
     
     
         9 . The communications apparatus of  claim 1  wherein the first matching network comprises a controllable first matching network for presenting a controllable load impedance to the first power amplifier responsive to a power-related parameter of the first power amplifier, and wherein the second matching network comprises a controllable second matching network for presenting a controllable load impedance to the second power amplifier responsive to a power-related parameter of the second power amplifier. 
     
     
         10 . A communications apparatus comprising:
 a first antenna having a resonant frequency in a first frequency band;   a second antenna having a resonant frequency in a second frequency band;   a first and a second power amplifier respectively supplying a first and a second signal for transmitting;   a switching element for switchably supplying the first or the second signal for transmitting to the first antenna or to the second antenna responsive to the frequency of the first and the second signal for transmitting; and   an impedance controller for controlling the impedance of the first and the second antennas responsive to a power-related parameter.   
     
     
         11 . The communications apparatus of  claim 10  further comprising a first and a second receiver connected to the switching element for supplying a signal received at the first or the second antenna to the first or the second receiver responsive to a frequency of the signal received at the first or the second antenna. 
     
     
         12 . The communications apparatus of  claim 10  wherein the impedance controller controls the impedance of the first and the second antennas responsive to the respective power related parameter of the first and the second power amplifier to control the power added efficiency or the efficiency of the first and the second power amplifiers. 
     
     
         13 . The communications apparatus of  claim 10  further comprising a first and a second matching network disposed between the respective first and second power amplifiers and the switching element, the first and the second matching networks and the impedance controller operative to control the power added efficiency or the efficiency of the first and the second power amplifiers. 
     
     
         14 . The communications apparatus of  claim 10  wherein the first and the second matching networks and the impedance controller cooperate to control a load impedance of the first and the second power amplifiers to broaden a signal bandwidth of the first and the second signals for transmitting. 
     
     
         15 . The communications apparatus of  claim 10  wherein the impedance controller controls the impedance of the first and the second antennas by controlling lumped reactive components or distributed reactive components operative with the first or the second antenna. 
     
     
         16 . A communications apparatus comprising:
 a first antenna having a resonant frequency in a first frequency band;   a second antenna having a resonant frequency in a second frequency band, the first and the second antennas presenting an antenna impedance less than about 50 ohms at a respective resonant frequency;   a signal combiner connected to the first and the second antennas;   a first and a second power amplifier respectively supplying a first and a second signal for transmitting; and   a first switching element for switchably supplying the first or the second signal for transmitting to the signal combiner, the signal combiner supplying the first or the second signal for transmitting to the first antenna or to the second antenna responsive to the frequency of the first and the second signal for transmitting; and   a first and a second matching network disposed between the respective first and second power amplifiers and the switching element, the first and the second matching networks operative to control the power added efficiency or the efficiency of the first and the second power amplifiers.   
     
     
         17 . The communications apparatus of  claim 16  further comprising a first and a second receiver connected to the first switching element for supplying a signal received at the first or the second antenna to the first or the second receiver responsive to a frequency of the signal received at the first or the second antenna. 
     
     
         18 . The communications apparatus of  claim 16  wherein the first and the second matching networks control the power added efficiency or the efficiency of the first and the second power amplifiers according to a power-related parameter. 
     
     
         19 . The communications apparatus of  claim 18  wherein the power-related parameter comprises a power amplifier output power, an operating frequency of the communications apparatus or a voltage standing wave ratio. 
     
     
         20 . An antenna for use in a communications device, comprising:
 one or more resonant elements presenting a first resonant frequency responsive to operation of the communications device in a first frequency band, wherein the first resonant frequency is within a highest frequency band in which the communications device is capable of operating; and   an antenna controller for controlling one or more antenna operating parameters to present a second resonant frequency responsive to operation of the communications device in a second frequency band.   
     
     
         21 . The antenna of  claim 20  wherein the operating parameters comprise one of resonant frequency and antenna terminal impedance. 
     
     
         22 . The antenna of  claim 20  wherein operation in the first frequency band is at a first power level and operation in the second frequency band is at a second power level different from the first power level.