Low loss transmitter receiver switch with transformer matching network

Patent metadata

Field	Value
Publication number	US-2021044318-A1
Application number	US-202016931462-A
Country	US
Kind code	A1
Filing date	Jul 17, 2020
Priority date	Sep 6, 2018
Publication date	Feb 11, 2021
Grant date	—

Abstract

A transmit receive switch (TRSW) system is disclosed. The system has a transmission line, a transformer based matching network, a shunt switch, an amplifier and circuitry. The transmission line is connected to an antenna port. The transformer based matching network is connected to the transmission line and has a first coil and a second coil, wherein the second coil is connected to the transmission line. The amplifier can be configured as a shunt switch when inactive. The shunt switch, including the amplifier configured as the shunt switch, can be connected to the first coil of the transformer based matching network. The circuitry is configured to cause the shunt switch to be ON during an inactive mode and create a short across the first coil. Combined, the length of transmission line needed to complete the impedance transformation is reduced, thereby lowering the overall insertion loss of the transmit/receive switch.

First claim

1 - 20 . (canceled)

21 . A system comprising:
a transmitter configured to send a transmit signal for transmission to an antenna port; and a receiver configured to receive a receive signal via the antenna port, wherein the transmitter comprises:
a power amplifier for amplifying the transmit signal;
a first impedance matching network coupled to an output of the power amplifier and the antenna port; and
a first shunt switch coupled to the output of the power amplifier, wherein the first shunt switch is configured to disable the transmitter based on a receive mode and enable the transmitter based on a transmit mode.

22 . The system of claim 21 , wherein the first impedance matching network is a transformer-based matching network having a first coil and a second coil, wherein the first coil is coupled to the output of the power amplifier and the second coil is coupled to a transmission line connected to the antenna port.

23 . The system of claim 22 , wherein the first shunt switch is connected in parallel to the first coil of the transformer-based matching network.

24 . The system of claim 22 , wherein the transmission line has a length of less than λ/4.

25 . The system of claim 22 , wherein the transmission line and the transformer-based matching network provide a combined impedance transformation of 180 degrees of λ/4.

26 . The system of claim 22 , wherein the first shunt switch is configured to create a low resistance short across the first coil during the receive mode.

27 . The system of claim 21 , wherein the receiver comprises:
a low noise amplifier for amplifying the receive signal; a second impedance matching network coupled to an input of the low noise amplifier and the antenna port; and a second shunt switch coupled to the input of the low noise amplifier, wherein the second shunt switch is configured to disable the receiver based on the transmit mode and enable the receiver based on the receive mode.

28 . The system of claim 27 , wherein the second impedance matching network is a transformer-based matching network having a first coil and a second coil, wherein the first coil is coupled to a transmission line connected to the antenna port and the second coil is coupled to the input of the low noise amplifier.

29 . The system of claim 28 , wherein the second shunt switch is connected in parallel to the second coil of the transformer-based matching network.

30 . The system of claim 28 , wherein the transmission line has a length of less than λ/4.

31 . The system of claim 28 , wherein the transmission line and the transformer-based matching network provide a combined impedance transformation of 180 degrees of λ/4.

32 . The system of claim 28 , wherein the second shunt switch is configured to create a low resistance short across the second coil during the transmit mode.

33 . The system of claim 28 , further comprising a control circuitry configured to control timing of the first shunt switch and the second shunt switch when changing between the transmit mode and the receive mode.

34 . The system of claim 21 , wherein the first shunt switch is incorporated into the power amplifier.

35 . The system of claim 34 , wherein gate and drain voltages of the power amplifier are switched depending on whether the system is in the transmit mode or a receive mode.

36 . The system of claim 35 , wherein in the transmit mode, a gate of the power amplifier is connected to a nominal bias voltage while a drain of the power amplifier is connected to V DD , and in the receive mode the gate of the power amplifier is pulled up to V DD while the drain of the power amplifier is tied to ground.

37 . The system of claim 36 , further comprising a power inverter to perform switching operation between V DD and ground.

38 . A method of operating a transmit receive switch in a system, the method comprising:
providing a first impedance matching network to an output of a power amplifier in a transmitter and an antenna port, and a first shunt switch coupled to the output of the power amplifier; and controlling the first shunt switch to disable a transmitter based on a receive mode and enable the transmitter based on a transmit mode.

39 . The method of claim 38 further comprising:
providing a second impedance matching network to an input of the low noise amplifier in a receiver and the antenna port, and a second shunt switch coupled to the input of a low noise amplifier; and
controlling the second shunt switch to disable a receiver based on the transmit mode and enable the receiver based on the receive mode.

Assignees

• Intel Corp

Inventors

• Callender Steven
• Hull Christopher
• Pellerano Stefano
• Shin Woorim
• Kwok Ka Chun

Classifications

• H03F2200/294

  the amplifier being a low noise amplifier [LNA] · CPC title

• H04B1/48 Primary

  in circuits for connecting transmitter and receiver to a common transmission path, e.g. by energy of transmitter {(H04B1/46 takes precedence)} · CPC title

• H03F3/21

  with semiconductor devices only {(H03F3/245 takes precedence)} · CPC title

• H03F1/565

  using inductive elements · CPC title

• H04B1/44 Primary

  Transmit/receive switching · CPC title