Reconfigurable, bi-directional, multi-band front end for a hybrid beamforming transceiver
Designs and techniques to enhance power-efficiency and incorporate new features in millimeter-wave MIMO transceivers are described. A new mechanism for built-in dual-band, per-element self-interference cancellation (SIC) is introduced to enable multi-antenna frequency-division duplex (FDD) and full-duplex (FD) operation. Additionally, several innovative circuit concepts are introduced, including low-loss wideband antenna interface design, dual-band power combining PA, dual-band RF-SIC design, and bi-directional MIMO signal.
1. A beamforming transceiver, comprising:
a plurality of digital transmit/receive modules configured as receivers; and
a plurality of digital transmit/receive modules configured as transmitters;
wherein each digital transmit/receive module comprises:
an amplifier coupled to an antenna;
one or more bi-directional complex-valued weighting modules, coupled to the amplifier; and
one or more frequency converters coupled to the one or more weighting modules;
the transceiver further comprising self-interference cancelling circuitry for cancellation of leakage of a transmitted signal to a received signal, the self-interference cancelling circuitry forming a self-interference cancellation signal by combining an input to each of the transmitters and injecting the self-interference cancellation signal into each of the receivers.
2. The beamforming transceiver of claim 1 wherein a received signal and the self-interference cancellation signal have similar frequency responses at the resonant frequencies at bands of interest.
3. The beamforming transceiver of claim 1 wherein, for the digital transmit/receive modules configured as receivers, one of the complex weighting modules is configured for reception and another of the complex weighting modules is used to inject the weighted self-interference cancellation signal.
4. The beamforming transceiver of claim 1 wherein the self-interference cancellation signal is independently weighted from a received signal.
5. The beamforming transceiver of claim 1 wherein, for the digital transmit/receive modules configured as transmitters, one of the complex weighting modules is configured for transmitting and other complex weighting modules are left unused.
6. The beamforming transceiver of claim 1 wherein the amplifier comprises a high-power transmit amplifier for when the transmit/receive module is configured as a transmitter and a low-power amplifier for when the transmit/receive module is configured as a receiver.
7. The beamforming transceiver of claim 6 wherein the high-power transmit amplifier is switched off when the transmit/receive module is configured as a receiver and further wherein the low-power amplifier is switched off when the transmit/receive modules configured as a transmitter.
8. A beamforming transceiver, comprising:
a plurality of tiled blocks of fully-connected hybrid transmit/receive modules configured as transmitters or receivers;
wherein each block fully-connected hybrid transmit/receive module comprises:
an amplifier coupled to an antenna;
one or more bi-directional complex-valued weighting modules, coupled to the amplifier; and
one or more splitters/combiners coupled to the one or more weighting modules;
the transceiver further comprising self-interference cancelling circuitry for cancellation of leakage of a transmitted signal to a received signal, the self-interference cancelling circuitry forming a self-interference cancellation signal by combining an input to each of the transmitters and injecting the self-interference cancellation signal into each of the receivers.
9. The beamforming transceiver of claim 8 wherein a received signal and the self-interference cancellation signal have similar frequency responses at the resonant frequencies at bands of interest.
10. The beamforming receiver of claim 8 wherein the self-interference cancellation signal is independently weighted from a received signal.
11. The beamforming transceiver of claim 8 wherein a first portion of the plurality of tiled blocks of the transmit/receive modules are configured as receivers and wherein a second portion of the plurality of tiled blocks of transmit/receive modules are configured as transmitters.
12. The beamforming transceiver of claim 8 wherein all of the plurality of tiled blocks of the transmit/receive modules are configured as receivers.
13. The beamforming transceiver of claim 8 wherein all of the plurality of tiled blocks of the transmit/receive modules are configured as transmitters.
14. The beamforming transceiver of claim 8 wherein, for the tiled blocks configured as receivers, one of the complex weighting modules of each of the fully-connected hybrid transmit/receive modules is configured for reception and another of the complex weighting modules is used to inject the weighted self-interference cancellation signal.
15. The beamforming receiver of claim 8 wherein, for the tiled blocks configured as transmitters, one of the complex weighting modules of each of the fully-connected hybrid transmit/receive modules is configured for transmitting and other complex weighting modules are left unused.
16. The beamforming transceiver of claim 8 wherein the amplifier comprises a high-power transmit amplifier for when the transmit/receive module is configured as a transmitter and a low-power amplifier for when the transmit/receive module is configured as a receiver.
17. The beamforming transceiver of claim 16 wherein the high-power transmit amplifier is switched off when the transmit/receive module is configured as a receiver and further wherein the low-power amplifier is switched off when the transmit/receive modules configured as a transmitter.