MULTI-CHANNEL RADIO FREQUENCY FRONT END CIRCUIT WITH FULL TRANSMIT AND RECEIVE DIVERSITY FOR MULTI-PATH MITIGATION

• US 20100225414A1
• Filed: 07/07/2009
• Published: 09/09/2010
• Est. Priority Date: 03/03/2009
• Status: Abandoned Application

• Current Assignee: Skyworks Solutions Incorporated
• Original Assignee: Skyworks Solutions Incorporated
• Inventors: Gorbachov, Oleksandr
• Application Number:
  US12/498,912
• Publication Number:
  US 20100225414A1
• Time in Patent Office: Days
• US Class Current: 333/101
• CPC Class Codes: H04B 1/48 in circuits for connecting transmitter and receiver to a common transmission path, e.g. by energy of transmitter H04B1/46 takes precedence
• CPC Class Codes: H04B 7/0602 using antenna switching H04B7/0686 takes precedence; antenna beam directivity switching H01Q3/24
• CPC Class Codes: H04B 7/0817 with multiple receivers and antenna path selection

Abstract

A front end circuit for coupling a plurality of antennas to a multi-channel time domain duplex RF transceiver is disclosed. The front end circuit has a first transmit port, a first receive chain primary port, a first receive chain secondary ports, and a first antenna port connectable to a first one of the plurality of antennas. The front end circuit also has a second transmit port, a second receive chain primary port, and a second receive chain secondary port connectable to a second one of the plurality of antennas. A first switch has terminals connected to the first transmit port, the first receive chain primary port, and the second receive chain secondary port, as well as a common terminal that is connected to the first antenna port. Additionally, the front end circuit has a second switch that has terminals connected to the second transmit port, the second receive chain primary port and the first receive chain secondary port, and a common terminal connected to the second antenna port.

Claims

1. A front end circuit for coupling a plurality of antennas to a multi-channel radio frequency (RF) transceiver, the front end circuit comprising:

first and second transmit chains;

first and second power dividers;

first and second receive chains each including a first split and a second split interconnected to a common by a respective one of the first and second power dividers;

an antenna switch circuit connectable to a first and a second one of the plurality of antennas;

a first network selectively connecting the antenna switch circuit to the first transmit chain and the first receive chain; and

a second network selectively connecting the antenna switch circuit to the second transmit chain and the second receive chain.

2. The front end circuit of claim 1, wherein the antenna switch circuit has a first port connectable to the first antenna, a second port connectable to the second antenna, a third port connectable to the first network, and a fourth port connectable to the second network.

3. The front end circuit of claim 2, wherein:

the first port and the second port define antenna-side ports;

the third port and the fourth port define circuit-side ports;

the antenna switch circuit selectively connects pairings of the antenna-side ports to the circuit-side ports.

4. The front end circuit of claim 3, wherein the antenna switch circuit is a double-pole, double-throw switch.

5. The front end circuit of claim 2, wherein in a first operational mode of the antenna switch circuit, the first port is connected to the third port and the second port is connected to the fourth port.

6. The front end circuit of claim 2, wherein in a second operational mode of the antenna switch circuit, the first port is connected to the fourth port and the second port is connected to third port.

7. The front end circuit of claim 1, wherein the RF transceiver has a first transmit line, a first primary receive line, a first secondary receive line, a second transmit line, a second primary receive line, and a second secondary receive line.

8. The front end circuit of claim 7, wherein:

the first transmit chain is connectable to a first transmit line; and

the second transmit chain is connectable to the second transmit line.

9. The front end circuit of claim 7, wherein:

the first split of the first receive chain is connectable to the first primary receive line; and

the second split of the second receive chain is connectable to the second secondary receive line.

10. The front end circuit of claim 7, wherein:

the first split of the second receive chain is connectable to the second primary receive line; and

the second split of the second receive chain is connectable to the first secondary receive line.

11. The front end circuit of claim 7, wherein:

the first transmit line, the first primary receive line, and the first secondary receive line are associated with a first transceiver channel having a first operating frequency; and

the second transmit line, the second primary receive line, and the second secondary receive line are associated with a second transceiver channel having a second operating frequency different from the first operating frequency.

12. The front end circuit of claim 1, wherein the first network and the second network are a single-pole, double throw switch with a common terminal, a first terminal, and a second terminal, the common terminals being connectable to the respective one of the antennas, the first terminals being connectable to the respective one of the transmit chains, and the second terminals being connectable to the respective one of the receive chains.

13. The front end circuit of claim 1, further comprising:

a first band-pass filter coupled to the first antenna; and

a second band-pass filter coupled to the second antenna.

14. The front end circuit of claim 13, wherein:

the first band-pass filter is connected to the third port of the antenna switch circuit and the first network; and

the second band-pass filter is connected to the fourth port of the antenna switch circuit and the second network.

15. The front end circuit of claim 13, wherein:

the first band-pass filter is connected to the first port of the antenna switch circuit and the first antenna; and

the second band-pass filter is connected to the second port of the antenna switch circuit and the second antenna.

16. The front end circuit of claim 1, wherein the transceiver complies with the Wireless Access for Vehicle Environments (WAVE) standard and includes a control channel corresponding to a one of the channels and a service channel corresponding to another one of the channels.

17. An RF front end circuit for coupling antennas to a transceiver having a first operational channel and a second operational channel, each of the first and second operational channels including a transmit line, a first receive line and a second receive line, the front end circuit comprising:

a first antenna chain and a second antenna chain each having;

a transmit mode connecting the transmit line to a one of the antennas;

a first receive mode connecting a one of the receive lines of one of the operational channels to the one of the antennas;

a second receive mode connecting a one of the receive lines of a different one of the operational channels to the one of the antennas; and

a third receive mode connecting the one of the receive lines of the one of the operational channels and the one of the receive lines of the different one of the operational channels to the one of the antennas;

wherein the transmit mode of one antenna chain is simultaneously active with the second receive mode of the other antenna chain.

18. The front end circuit of claim 17, wherein the transmit mode of the first antenna chain is exclusive of the transmit mode of the second antenna chain.

19. The front end circuit of claim 17, wherein:

the transmit mode of the first antenna chain is exclusive of the receive modes of the first antenna chain; and

the transmit mode of the second antenna chain is exclusive of the receive modes of the second antenna chain.