Multiplexing radio frequency signals

Abstract

The present disclosure is directed to a system and method for multiplexing radio frequency signals. In some implementations, a system includes a host coupling module, a plurality of antennas, and a processing module. The host coupling module is configured to receive and transmit RF signals through a wired connection. The plurality of antennas are configured to wirelessly transmit RF signals and receive RF signals from RFID tags. The processing module is configured to selectively switch between the plurality of antennas for communication with the RFID tags using the host coupling module and backscatter at least a portion of the received RF signals through the wired connection to communicate information independent of an internal power supply.

1 - 10 . (canceled) 
     
     
         11 . A radio frequency identification (RFID) multiplexer system, comprising:
 a plurality of multiplexers connected in series including an initial multiplexer, the initial multiplexer comprising:
 a port configured to receive RF signals from an RFID host; and 
 a communication module connected to the port and configured to demodulate the received RF signals to baseband frequency signals; 
   wherein at least one of the plurality of multiplexers is configured to selectively switch signals transmitted through an output port to subsequent multiplexers, the signals including RF signals and DC power.   
     
     
         12 . The RFID multiplexer system of  claim 11 , wherein the communication module is configured to backscatter RF data via amplitude modulation or phase modulation. 
     
     
         13 . The RFID multiplexer system of  claim 12 , wherein the backscattered RF data identifies information associated with one or more operating parameters of one of the plurality of RFID multiplexers. 
     
     
         14 . The RFID multiplexer system of claim  1 , wherein the communication module further comprises a tag emulator module. 
     
     
         15 . The RFID multiplexer system of claim  1 , further comprising a control module configured to selectively switch between a plurality of antennas based, at least in part, on received RF signals. 
     
     
         16 . The RFID multiplexer system of  claim 11 , wherein the initial multiplexer is connected to a second RFID multiplexer through a second single wired connection such that DC and RF signals received from the RFID host can be passed to the second RFID multiplexer. 
     
     
         17 . The RFID multiplexer system of  claim 16 , wherein the second single wired connection comprises a coaxial cable. 
     
     
         18 . A method of controlling an RFID multiplexer, comprising:
 receiving RF signals through a single wired connection to an RFID host, wherein the received RF signals include signals for wireless transmission and control signals for antenna switching;   transmitting to a plurality of multiplexers in series, Direct Current (DC) components combined with the received RF signals;   providing power for the multiplexer using the DC components;   transmitting to the plurality of multiplexers through the wired connection, the RF signals for wireless transmission and the control signals for antenna switching; and   backscattering at least a portion of the received RF signals in response to identifying requests for information, wherein the backscattered RF signals identify the detected components of the RF signals received from the RFID host.   
     
     
         19 . The method of  claim 18 , further comprising:
 demodulating at least a portion of the received RF signals to baseband frequency signals; and   selecting one antenna to wirelessly transmit at least a portion of the received RF signals based at least in part on the baseband frequency signals.   
     
     
         20 . The method of claim  10 , wherein the baseband frequency signals are converted to digital signals. 
     
     
         21 . A radio frequency identification (RFID) multiplexer comprising:
 a port configured to perform at least one of the following operations: receive RF signals from an RFID host and provide RF signals and DC components to a second RFID multiplexer;   a receiver module configured to demodulate received RF signals into baseband frequency signals;   a module configured to backscatter a response to at least a portion of the received RF signals through the port;   a control module configured to perform at least one of the following operations:   receive baseband frequency signals, control a switching module, and backscatter control signals to the tag emulator module;   
       wherein the switching module is configured to selectively switch between antennas. 
     
     
         22 . The RFID multiplexer of  claim 21 , wherein the control module further comprises at least one processor. 
     
     
         23 . The RFID multiplexer of  claim 22 , wherein the baseband frequency signals include instructions to be executed by the at least one processor. 
     
     
         24 . The RFID multiplexer of  claim 21 , wherein the baseband frequency signals are converted to digital baseband signals by the control module. 
     
     
         25 . The RFID multiplexer of  claim 21 , further comprising a power tap module.