Multiband RF Device

Abstract

A device or system for transmission and reception for voice or data communication applications. The device or system is capable of duplex operation and adapted to operate in an environment using a plurality of frequency bands. The present disclosure also relates to a communication means including a transmitter and receiver arrangement and to antennas.

1 . A device for signal transmission, adapted for operation in a plurality of frequency bands, comprising:
 a wide-band tunable modulation stage adapted for providing signals over the plurality of frequency bands   a first filter, comprising frequency selective elements selective for each of the plurality of frequency bands to receive a transmission signal from the wide-band tunable modulation stage and to provide a filtered signal, and   a final power amplifier stage adapted to receive the filtered signal,   
       wherein the signal is directed from the wide-band tunable modulation stage through the first filter to the final power amplifier stage. 
     
     
         2 . The device of  claim 1  wherein the final power amplifier stage provides output to a second filter, wherein the second filter is tunable. 
     
     
         3 . The device of  claim 1  wherein the first filter comprises a switch. 
     
     
         4 . The device of  claim 1  wherein a pre-power amplifier is positioned in the signal path between the modulation stage and the first filter. 
     
     
         5 . The device of  claim 1  wherein the final power amplifier stage comprises but one power amplifier. 
     
     
         6 . The device of  claim 1  where the frequency selective elements are selective for at least one of the frequencies 850, 900, 1800, 1900 and 2100 MHz. 
     
     
         7 . The device of  claim 1  where signals from frequency selective elements are grouped and directed to power amplifiers in the power amplifier stage, whereby each power amplifier receives signals from at least two of the frequency selective elements. 
     
     
         8 . A transmitter and receiver arrangement for communication applications, comprising a transmitter and a receiver adapted to operate in a plurality of frequency bands, comprising a device according to  claim 1 . 
     
     
         9 . The transmitter and receiver arrangement of  claim 8  wherein the signal from the final power amplifier stage is directed to at least one circulator. 
     
     
         10 . The transmitter and receiver arrangement of  claim 8  or  9  wherein the signal from the final power amplifier stage is directed to multiple circulators, each adapted to a group of one or more of the frequencies selected by the frequency selective elements. 
     
     
         11 . The transmitter and receiver arrangement of  claim 10 , wherein a transmit path is adapted to be connected to a first antenna for transmission and wherein a receive path is adapted to be connected to a second antenna for reception. 
     
     
         12 . The transmitter and receiver arrangement of  claim 10  wherein multiple low-Q filters are disposed in a transmit path following the power amplifier stage, each adapted to operate on one or more of the frequency bands used for duplex operation. 
     
     
         13 . The transmitter and receiver arrangement of  claim 10  wherein a filter with directional attenuation characteristics is disposed between transmitter and receiver. 
     
     
         14 . The transmitter and receiver arrangement of  claim 10  in which attenuation between transmitter and receiver is achieved by using multiple narrow-band circulators with directional attenuation characteristics, each adapted to operate on one or more of the frequency bands used for duplex operation. 
     
     
         15 . A method of transmitting a signal in a plurality of frequency bands wherein the signal is directed from a wide-band tunable modulation stage adapted for providing signals over the plurality of frequency bands, to a first filter, comprising frequency selective elements selective for each of the plurality of frequency bands to receive a transmission signal from the modulation stage and to provide a filtered signal, and then to a final power amplifier stage adapted to receive the filtered signal.