Switchable rf transmit/receive multiplexer

Abstract

A switchable RF transmit/receive (TX/RX) multiplexer, which includes a group of RF TX bandpass filters, a group of RF TX switching elements, and a group of RF RX bandpass filters; is disclosed. The group of RF TX bandpass filters includes a first RF TX bandpass filter and a second RF TX bandpass filter, such that each of the first RF TX bandpass filter and the second RF TX bandpass filter is coupled to a first filter connection node. The group of RF TX switching elements includes a first RF TX switching element coupled between the first filter connection node and a first common connection node, which is coupled to a first RF antenna. Each of the group of RF RX bandpass filters is coupled to the first common connection node.

What is claimed is: 
     
         1 . A switchable radio frequency (RF) transmit/receive (TX/RX) multiplexer comprising:
 a plurality of RF TX bandpass filters comprising a first RF TX bandpass filter coupled to a first filter connection node and a second RF TX bandpass filter coupled to a second filter connection node distinct from the first filter connection node;   a first plurality of RF TX switching elements comprising:
 a first RF TX switching element coupled between the first filter connection node and a first common connection node, which is coupled to a first RF antenna; and 
 a second RF TX switching element coupled between the second filter connection node and the first common connection node; and 
   a first plurality of RF RX bandpass filters, wherein each of the first plurality of RF RX bandpass filters is coupled to the first common connection node without an intervening switching element.   
     
     
         2 . The switchable RF TX/RX multiplexer of  claim 1  wherein the plurality of RF TX bandpass filters further comprises a third RF TX bandpass filter and the first plurality of RF TX switching elements further comprises a third RF TX switching element, such that the third RF TX switching element is coupled between the third RF TX bandpass filter and the first common connection node. 
     
     
         3 . The switchable RF TX/RX multiplexer of  claim 2  wherein a fourth RF TX bandpass filter of the plurality of RF TX bandpass filters is coupled to the first filter connection node. 
     
     
         4 . The switchable RF TX/RX multiplexer of  claim 1  wherein the plurality of RF TX bandpass filters further comprises a third RF TX bandpass filter coupled to the first common connection node. 
     
     
         5 . The switchable RF TX/RX multiplexer of  claim 1  further comprising a plurality of RF phase-shifting circuits, which comprises a first RF phase-shifting circuit and a second RF phase-shifting circuit, wherein the first RF phase-shifting circuit is coupled between the first RF TX bandpass filter and the first filter connection node, and the second RF phase-shifting circuit is coupled between the second RF TX bandpass filter and the first filter connection node. 
     
     
         6 . The switchable RF TX/RX multiplexer of  claim 1  wherein the plurality of RF TX bandpass filters further comprises a third RF TX bandpass filter, which is coupled to the first filter connection node, and a fourth RF TX bandpass filter, which is coupled to the second filter connection node. 
     
     
         7 . The switchable RF TX/RX multiplexer of  claim 6  further comprising a plurality of RF phase-shifting circuits, which comprises a first RF phase-shifting circuit, a second RF phase-shifting circuit, a third RF phase-shifting circuit, and a fourth RF phase-shifting circuit, wherein:
 the first RF phase-shifting circuit is coupled between the first RF TX bandpass filter and the first filter connection node; 
 the second RF phase-shifting circuit is coupled between the second RF TX bandpass filter and the second filter connection node; 
 the third RF phase-shifting circuit is coupled between the third RF TX bandpass filter and the first filter connection node; and 
 the fourth RF phase-shifting circuit is coupled between the fourth RF TX bandpass filter and the second filter connection node. 
 
     
     
         8 . The switchable RF TX/RX multiplexer of  claim 6  further comprising a first plurality of RF phase-shifting circuits and a first plurality of phase-shift switching elements, wherein each of the first plurality of phase-shift switching elements is coupled between a corresponding one of the first plurality of RF phase-shifting circuits and the first common connection node. 
     
     
         9 . The switchable RF TX/RX multiplexer of  claim 1  further comprising a first plurality of RF phase-shifting circuits and a first plurality of phase-shift switching elements, wherein each of the first plurality of phase-shift switching elements is coupled between a corresponding one of the first plurality of RF phase-shifting circuits and the first common connection node. 
     
     
         10 . The switchable RF TX/RX multiplexer of  claim 1  wherein RF system control circuitry is configured to select one of a plurality of RF TX signals using a function configuration signal, such that the switchable RF TX/RX multiplexer is configured to filter and forward the one of the plurality of RF TX signals to the first common connection node using one of the plurality of RF TX bandpass filters. 
     
     
         11 . The switchable RF TX/RX multiplexer of  claim 1  configured to receive and process a plurality of first antenna, RF RX signals via the first RF antenna to provide a first plurality of upstream RF RX signals using the first plurality of RF RX bandpass filters. 
     
     
         12 . The switchable RF TX/RX multiplexer of  claim 11  wherein the first plurality of upstream RF RX signals are receive downlink carrier aggregation (RXDLCA) signals. 
     
     
         13 . The switchable RF TX/RX multiplexer of  claim 11  further comprising a second plurality of RF RX bandpass filters and further configured to receive and process a plurality of second antenna, RF RX signals via a second RF antenna to provide a second plurality of upstream RF RX signals using the second plurality of RF RX bandpass filters. 
     
     
         14 . The switchable RF TX/RX multiplexer of  claim 1  further comprising antenna switching circuitry, wherein each of the first plurality of RF RX bandpass filters is coupled to the first common connection node via the antenna switching circuitry, and the antenna switching circuitry is coupled between the first RF TX switching element and the first common connection node. 
     
     
         15 . The switchable RF TX/RX multiplexer of  claim 14  wherein RF system control circuitry is configured to select connectivity of the antenna switching circuitry between the first common connection node and the first plurality of RF RX bandpass filters, and is further configured to select connectivity of the antenna switching circuitry between the first common connection node and the first plurality of RF TX switching elements using a function configuration signal. 
     
     
         16 . The switchable RF TX/RX multiplexer of  claim 14  wherein the antenna switching circuitry is further coupled between a second common connection node and the first plurality of RF RX bandpass filters, and is additionally coupled between the second common connection node and the first plurality of RF TX switching elements. 
     
     
         17 . The switchable RF TX/RX multiplexer of  claim 16  further comprising a second plurality of RF RX bandpass filters, wherein the antenna switching circuitry is further coupled between the first common connection node and the second plurality of RF RX bandpass filters, and is additionally coupled between the second common connection node and the second plurality of RF RX bandpass filters. 
     
     
         18 . The switchable RF TX/RX multiplexer of  claim 17  wherein a passband of each of the first plurality of RF RX bandpass filters is essentially equivalent to a corresponding passband of each of the second plurality of RF RX bandpass filters. 
     
     
         19 . The switchable RF TX/RX multiplexer of  claim 17  further comprising a third plurality of RF RX bandpass filters, wherein the antenna switching circuitry is further coupled between the first common connection node and the third plurality of RF RX bandpass filters, and is additionally coupled between the second common connection node and the third plurality of RF RX bandpass filters. 
     
     
         20 . The switchable RF TX/RX multiplexer of  claim 16  further comprising a second plurality of RF TX switching elements, wherein the antenna switching circuitry is further coupled between the first common connection node and the second plurality of RF TX switching elements, and is additionally coupled between the second common connection node and the second plurality of RF TX switching elements.