Reconfigurable Feed-Forward for Electrical Balance Duplexers (EBD)

Abstract

Systems, methods, and devices for reducing insertion loss and/or swapping transmitter (TX) and receiver (RX) frequencies in an electrical balance duplexer (EBD) used in a transceiver device for frequency division duplexing (FDD) applications are provided. Feed-forward receiver path from the antenna to a low noise amplifier (LNA) and a feed-forward path from the antenna to a power amplifier (PA) of the EBD may be used for reducing insertion loss of the RX and TX signals. In some embodiments, switches may be used to selectively alter operational modes for varied levels of isolation and/or swapping of TX and RX frequencies.

1 . An electrical balance duplexer of a transceiver device, the electrical balance duplexer comprising:
 an antenna configured to send transmission signals over a first frequency and receive reception signals over a second frequency;   a low noise amplifier configured to amplify the reception signals from the antenna;   a power amplifier configured to amplify the transmission signals to the antenna;
 a hybrid transformer configured to isolate the reception signals from the transmission signals communicated concurrently; 
 a first switch on a first path configured to couple the antenna to the low noise amplifier, the first switch configurable to decouple the antenna from the low noise amplifier and to couple the antenna to ground; and 
 a second switch on a second path configured to couple the power amplifier to the antenna, the second switch configurable to decouple the antenna from the power amplifier and to couple the antenna to ground. 
   
     
     
         2 . The electrical balance duplexer of  claim 1 , wherein decoupling the antenna from the low noise amplifier and the power amplifier and coupling the antenna to ground enables swapping the first frequency and the second frequency. 
     
     
         3 . The electrical balance duplexer of  claim 1 , wherein the first path comprises a third switch and a receiver frequency filter, the third switch configured to couple the low noise amplifier to the receiver frequency filter. 
     
     
         4 . The electrical balance duplexer of  claim 3 , wherein the third switch is configurable to decouple the low noise amplifier from the receiver frequency filter and to couple the low noise amplifier to the receiver frequency filter. 
     
     
         5 . The electrical balance duplexer of  claim 3 , wherein the third switch is configured to couple the low noise amplifier to the receiver frequency filter while the first switch is configured to couple the antenna to the ground to enable swapping the first frequency and the second frequency. 
     
     
         6 . The electrical balance duplexer of  claim 1 , wherein the second path comprises a fourth switch and a transmitter frequency filter, the fourth switch configured to couple the power amplifier to the transmitter frequency filter. 
     
     
         7 . The electrical balance duplexer of  claim 6 , wherein the fourth switch is configurable to decouple the power amplifier from the transmitter frequency filter and to couple the power amplifier to the transmitter frequency filter. 
     
     
         8 . The electrical balance duplexer of  claim 6 , wherein the fourth switch is configured to couple the power amplifier to the transmitter frequency filter while the first switch is configured to couple the antenna to the ground to enable swapping the first frequency and the second frequency. 
     
     
         9 . The electrical balance duplexer of  claim 1 , wherein a transmitter frequency filter in the second path is configured to filter the transmission signals prior to amplification by the power amplifier while the second switch is configured to couple the antenna to ground. 
     
     
         10 . The electrical balance duplexer of  claim 1 , wherein a receiver frequency filter in the first path is configured to filter the reception signals prior to amplification by the low noise amplifier while the first switch is configured to couple the antenna to ground. 
     
     
         11 . A method, comprising:
 determining that transmission signals are transmitted over a first frequency from an electrical balance duplexer and reception signals are received over a second frequency at the electrical balance duplexer;   receiving an indication to transmit the transmission signals over the second frequency and to receive the reception signals over the first frequency;   reconfiguring components of the electrical balance duplexer to swap the first frequency with the second frequency for transmitting the transmission signals and the second frequency with the first frequency for receiving the reception signals; and   transmitting the transmission signals over the second frequency and receiving the reception signals over the first frequency.   
     
     
         12 . The method of  claim 11 , wherein the indication is based at least in part on compatibility for the electrical balance duplexer to communicate with an electronic device external to the electrical balance duplexer. 
     
     
         13 . The method of  claim 12 , wherein the electronic device is configured to:
 transmit transmission signals from the electronic device over the first frequency to be received as the reception signals over the first frequency at the electrical balance duplexer, receive the transmission signals from the electrical balance duplexer over the second frequency to be received as the reception signals over the second frequency at the electronic device, or   both.   
     
     
         14 . The method of  claim 11 , wherein the indication is based at least in part on a frequency response threshold associated with transmitting the transmission signals, receiving the reception signals, or both. 
     
     
         15 . One or more non-transitory, computer-readable media comprising instructions that, when executed by one or more processors of a first electronic device, cause the one or more processors to:
 receive an indication to swap a first frequency for transmitting transmission signals from a transceiver device with a second frequency for receiving reception signals at the transceiver device;   in response to receiving the indication, configure the transceiver device to decouple an antenna of the transceiver device from a transmitter filter and a receiver filter;   configure the transceiver device to couple the antenna to ground; and   transmit the transmission signals over the second frequency and receive the reception signals over the first frequency.   
     
     
         16 . The non-transitory, computer-readable medium of  claim 15 , wherein the transceiver device comprises an electrical balance duplexer. 
     
     
         17 . The non-transitory, computer-readable medium of  claim 15 , wherein the instructions cause the one or more processors to:
 configure the transceiver device to couple a low noise amplifier of the transceiver device to the receiver filter;   configure the transceiver device to couple a power amplifier of the transceiver device to the transmitter filter; and   filter the reception signals via the receiver filter prior to amplification by the low noise amplifier and the transmission signals via the transmitter filter prior to amplification by the power amplifier while the antenna is configured to couple to ground.   
     
     
         18 . The non-transitory, computer-readable medium of  claim 15 , wherein the transceiver device comprises a first switch between the antenna and the receiver filter for configuring the transceiver device to swap the first frequency and the second frequency. 
     
     
         19 . The non-transitory, computer-readable medium of  claim 15 , wherein the transceiver device comprises a second switch between the antenna and the transmitter filter for configuring the transceiver device to swap the first frequency and the second frequency. 
     
     
         20 . The non-transitory, computer-readable medium of  claim 15 , wherein the indication is based at least in part on a frequency response threshold associated with transmitting the transmission signals, receiving the reception signals, or both.