| 摘要 |
Apparatus and methods of simultaneous transmission and reception in a single-antenna radio transceiver. The transceiver may be used, for instance, for communication between at least two terminals, by use of multiple intermediate recruited transceiver nodes. The recruited transceiver nodes receive a signal from a master mode, and then retransmit the signal to a receiver. The recruited transceiver nodes are designed to have reduced interference between the transmit channel and the received channel. In accordance with one aspect of the present application, embodiments can achieve more robust wireless communication between a transmitter and an over-the-horizon receiver. The robust wireless communication will have improved resistance to interference, including self-interference, and improved communication range. |
| 主权项 |
1. A method to reduce interference between an interfering transmitted signal and a received signal in a transceiver, comprising the steps of:
receiving a transmitter signal at a first port of a directional coupler; splitting the transmitter signal into a first transmit portion directed to a second port of the directional coupler, and a second transmit portion directed to a third port of the directional coupler, wherein the second port is coupled to an antenna and the third port is coupled to an adjustable impedance; filtering the second transmit portion by use of the adjustable impedance to produce a filtered second transmit portion; reflecting at least a portion of the filtered second transmit portion into the third port of the directional coupler; receiving an incoming signal at the second port of the directional coupler, the incoming signal including a received portion and a reflected portion, wherein the reflected portion is a partial reflection of the first transmit portion; combining the incoming signal at the second port of the directional coupler and the reflected signal at the third port of the directional coupler, to produce a combined signal at a fourth port of the directional coupler, and adjusting the adjustable impedance based on a spectral, temporal, and/or power characteristic of the transmitter signal and a spectral, temporal, and/or power characteristic of an impedance load coupled to the second port; wherein, in the combined signal, the reflected signal from the third port cancels at least a portion of the partial reflection of the first transmit portion from the second port; wherein the adjustable impedance produces a notch frequency rejection in the combined signal using ZCOMP, where ZCOMP is an impedance estimated by the equation
ZCOMP=b0+jb1(ω−ω0)+b2(ω−ω0)2+jb3(ω−ω0)3,where {bi}i=03 are real constants and ω is an angular frequency, the notch frequency centered at a carrier frequency of the transmitter signal, and ω0 is a nominal angular frequency. |
