On chip diversity antenna switch

• US 20040214528A1
• Filed: 06/12/2003
• Published: 10/28/2004
• Est. Priority Date: 04/25/2003
• Status: Active Grant

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Broadcom Corporation (Broadcom, Inc.)
• Inventors: Ibrahim, Brima B., Marholev, Bojko F., Khorram, Shahla
• Granted Patent: US 7,079,816 B2
• Time in Patent Office: Days
• US Class Current: 455/78
• CPC Class Codes: H04B 1/44 Transmit/receive switching

Abstract

An on chip diversity antenna switch includes a first switch, a second switch, a third switch, and a fourth switch. The first switch is operably coupled to a pin associated with a first antenna, to a transmit path and to receive a transmit receive (T/R) control signal. The second switch is operably coupled to the pin associated with the first antenna, to a receive path, and to receive the T/R control signal. The third switch is operably coupled to a pin associated with a second antenna, the transmit path, and to receive the T/R control signal. The fourth switch is operably coupled to the pin associated with the second antenna, to the receive path, and to receive the T/R control signal. Based on the T/R control signal, the first or second antenna is coupled to the transmit or receive path via a single switch.

Claims

1. An on-chip diversity antenna switch comprises:

a first switch operably coupled to a pin associated with a first antenna, to a transmit path, and to receive a T/R control signal;

a second switch operably coupled to the pin associated with first antenna, to a receive path, and to receive the T/R control signal;

a third switch operably coupled to a pin associated with a second antenna, to the transmit path, and to receive the T/R control signal;

a fourth switch operably coupled to the pin associated with the second antenna, to the receive path, and to receive the T/R control signal, wherein, when the T/R control signal is in a first state, the first switch is active to couple the pin associated with the first antenna to the transmit path, when the T/R control signal is in a second state, the second switch is active to couple the receive path to the pin associated with the first antenna, when the T/R control signal is in a third state, the third switch is active to couple the pin associated with the second antenna to the transmit path, and, when the T/R control signal is in a fourth state, the fourth switch is active to couple the pin associated with the second antenna to the transmit path.

2. The on-chip diversity antenna switch of claim 1, wherein each of the first, second, third, and fourth switches comprises a transistor.

3. The on-chip diversity antenna switch of claim 2 further comprises:

parasitic compensation circuit operably coupled to compensate for adverse affects induced by parasitics of the transistors.

4. The on-chip diversity antenna switch of claim 3, wherein the parasitic compensation circuit further comprises:

a first inductor operably coupled to the pin associated with the first antenna and to AC ground;

a second inductor operably coupled to the pin associated with the second antenna and to the AC ground;

a third inductor operably coupled to the transmit path and to the AC ground; and

a fourth inductor operably coupled to the receive path and to the AC ground.

5. The on-chip diversity antenna switch of claim 4 further comprises:

a bias voltage circuit operably coupled to provide a bias voltage that, at operating frequencies of the on-chip diversity antenna switch, functions as the AC ground.

6. An on-chip diversity antenna switch comprises:

first means for coupling a pin associated with a first antenna to a transmit path when a T/R control signal is in a first state;

second means for coupling the pin associated with first antenna to a receive path when the T/R control signal is in a second state;

third means for coupling a pin associated with a second antenna to the transmit path when the T/R control signal is in a third state; and

fourth means for coupling the pin associated with the second antenna to the receive path when the T/R control signal is in a fourth state.

7. The on-chip diversity antenna switch of claim 6, wherein at least one of the first, second, third, and fourth means comprises a transistor.

8. The on-chip diversity antenna switch of claim 7 further comprises:

parasitic compensation circuit operably coupled to compensate for adverse affects induced by parasitics of the transistors.

9. The on-chip diversity antenna switch of claim 8, wherein the parasitic compensation circuit further comprises at least one of:

a first inductor operably coupled to the pin associated with the first antenna and to AC ground;

a second inductor operably coupled to the pin associated with the second antenna and to the AC ground;

a third inductor operably coupled to the transmit path and to the AC ground; and

a fourth inductor operably coupled to the receive path and to the AC ground.

10. The on-chip diversity antenna switch of claim 9 further comprises:

a bias voltage circuit operably coupled to provide a bias voltage that, at operating frequencies of the on-chip diversity antenna switch, functions as the AC ground.

11. A radio frequency integrated circuit (RFIC) comprises:

transmit section operably coupled to convert baseband data into outbound radio frequency (RF) signals based on a transmit local oscillation;

receive section operably coupled to convert received RF signals into inbound baseband data based on a receive local oscillation; and

transmit/receive switch operably coupled to the transmit section and the receive section, wherein the transmit/receive switch includes;

a first switch operably coupled to a pin associated with a first antenna, to a transmit path, and to receive a T/R control signal;

a second switch operably coupled to the pin associated with first antenna, to a receive path, and to receive the T/R control signal;

a third switch operably coupled to a pin associated with a second antenna, to the transmit path, and to receive the T/R control signal;

a fourth switch operably coupled to the pin associated with the second antenna, to the receive path, and to receive the T/R control signal, wherein, when the T/R control signal is in a first state, the first switch is active to couple the pin associated with the first antenna to the transmit path, when the T/R control signal is in a second state, the second switch is active to couple the receive path to the pin associated with the first antenna, when the T/R control signal is in a third state, the third switch is active to couple the pin associated with the second antenna to the transmit path, and, when the T/R control signal is in a fourth state, the fourth switch is active to couple the pin associated with the second antenna to the transmit path.

12. The RFIC of claim 11, wherein each of the first, second, third, and fourth switches comprises a transistor.

13. The RFIC of claim 12 further comprises:

parasitic compensation circuit operably coupled to compensate for adverse affects induced by parasitics of the transistors.

14. The RFIC of claim 13, wherein the parasitic compensation circuit further comprises:

a first inductor operably coupled to the pin associated with the first antenna and to AC ground;

a second inductor operably coupled to the pin associated with the second antenna and to the AC ground;

a third inductor operably coupled to the transmit path and to the AC ground; and

a fourth inductor operably coupled to the receive path and to the AC ground.

15. The RFIC of claim 14 further comprises:

a bias voltage circuit operably coupled to provide a bias voltage that, at operating frequencies of the on-chip diversity antenna switch, functions as the AC ground.

16. A radio frequency integrated circuit (RFIC) comprises:

transmit section operably coupled to convert baseband data into outbound radio frequency (RF) signals based on a transmit local oscillation;

receive section operably coupled to convert received RF signals into inbound baseband data based on a receive local oscillation; and

transmit/receive switch operably coupled to the transmit section and the receive section, wherein the transmit/receive switch includes;

first means for coupling a pin associated with a first antenna to a transmit path when a T/R control signal is in a first state;

second means for coupling the pin associated with first antenna to a receive path when the T/R control signal is in a second state;

third means for coupling a pin associated with a second antenna to the transmit path when the T/R control signal is in a third state; and

fourth means for coupling the pin associated with the second antenna to the receive path when the T/R control signal is in a fourth state.

17. The RFIC of claim 16, wherein at least one of the first, second, third, and fourth means comprises a transistor.

18. The RFIC of claim 17 further comprises:

parasitic compensation circuit operably coupled to compensate for adverse affects induced by parasitics of the transistors.

19. The RFIC of claim 18, wherein the parasitic compensation circuit further comprises at least one of:

a first inductor operably coupled to the pin associated with the first antenna and to AC ground;

a second inductor operably coupled to the pin associated with the second antenna and to the AC ground;

a third inductor operably coupled to the transmit path and to the AC ground; and

a fourth inductor operably coupled to the receive path and to the AC ground.

20. The RFIC of claim 19 further comprises:

a bias voltage circuit operably coupled to provide a bias voltage that, at operating frequencies of the on-chip diversity antenna switch, functions as the AC ground.