Methods and transceivers for self-interference mitigation
The present disclosure relates to a transceiver comprising a transmitter with transformation circuitry configured to transform a frequency-domain transmit symbol from frequency domain to time domain to generate a time-domain transmit signal, a receiver with inverse transformation circuitry configured to transform a time-domain receive signal from time domain to frequency domain to generate a frequency-domain receive symbol, and self-interference cancellation circuitry configured to modify the frequency-domain receive symbol based on at least one frequency-domain transmit symbol and a frequency-domain crosstalk channel estimate of a crosstalk channel between the transmitter and the receiver.
1. A transceiver, comprising
a transmitter comprising transformation circuitry configured to transform a frequency-domain transmit symbol from frequency domain to time domain to generate a time-domain transmit signal;
a receiver comprising inverse transformation circuitry configured to transform a time-domain receive signal from time domain to frequency domain to generate a frequency-domain receive symbol; and
self-interference cancellation circuitry configured to modify the frequency-domain receive symbol based on at least one frequency-domain transmit symbol and a frequency-domain crosstalk channel estimate of a crosstalk channel between the transmitter and the receiver.
2. The transceiver of claim 1 , wherein the transformation circuitry is configured to transform the frequency-domain transmit symbol from frequency domain to time domain via one of an inverse Fourier transform, an inverse Wavelet transform, an inverse Laplace transform, an inverse Cosine transform, or a Filter bank, and
wherein the inverse transformation circuitry is configured to transform the time-domain transmit signal from time domain to frequency domain based on one of a Fourier transform, a Wavelet transform, a Laplace transform, an Cosine transform, or a Filter bank.
3. The transceiver of claim 1 , wherein the transceiver is a multicarrier transceiver, wherein a carrier frequency of a multicarrier time-domain transmit signal and a carrier frequency of a multicarrier time-domain receive signal are shifted by a frequency shift Δf, and
wherein the self-interference cancellation circuitry is configured to compute a crosstalk from a multicarrier transmit signal subcarrier n to a multicarrier receive signal subcarrier m based on a distance between the subcarriers n, m and based on the frequency shift Δf.
4. The transceiver of claim 3 , wherein the transceiver is an OFDM transceiver, wherein the self-interference cancellation circuitry is configured to compute the crosstalk from OFDM transmit signal subcarrier n to OFDM receive signal subcarrier m based on weighing the frequency-domain crosstalk channel estimate with an additional crosstalk coefficient comprising
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5. The transceiver of claim 3 , wherein a timing of the multicarrier time-domain transmit signal is shifted vis-à-vis the multicarrier time-domain receive signal by a time shift Δt, and wherein the self-interference cancellation circuitry is configured to compute a frequency-domain crosstalk coefficient corresponding to a crosstalk from the multicarrier time-domain transmit signal to the multicarrier time-domain receive signal based on a frequency-domain representation of the time shift Δt.
6. The transceiver of claim 5 , wherein the self-interference cancellation circuitry is configured to compute the frequency-domain crosstalk coefficient for a subcarrier with frequency f based on weighing the frequency-domain crosstalk channel estimate with an additional crosstalk coefficient corresponding to e −j2πfΔt .
7. The transceiver of claim 1 , wherein a transmit carrier frequency and a receive carrier frequency are shifted by a frequency shift Δf and a timing of a multicarrier transmit signal is shifted vis-à-vis a multicarrier receive signal by a time shift Δt, wherein the self-interference cancellation circuitry is configured to compute a crosstalk from a subcarrier n of the multicarrier transmit signal to a subcarrier m of the multicarrier receive signal based on a distance between the subcarriers n, m, the frequency shift Δf, and the time shift Δt.
8. The transceiver of claim 7 , wherein the transceiver is an OFDM transceiver, wherein the self-interference cancellation circuitry is configured to compute the crosstalk from the OFDM transmit signal to the OFDM receive signal based on
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denoting a normalized length of a temporal overlap between the OFDM transmit symbol and the OFDM receive symbol.
9. The transceiver of claim 1 , wherein the self-interference cancellation circuitry is configured to estimate the frequency-domain crosstalk channel estimate based on a transmission of pilot symbols.
10. A mobile device comprising:
a transceiver comprising:
a transmitter comprising transformation circuitry configured to transform a frequency-domain transmit symbol from frequency domain to time domain to generate a time-domain transmit signal;
a receiver comprising inverse transformation circuitry configured to transform a time-domain receive signal from time domain to frequency domain to generate a frequency-domain receive symbol; and
self-interference cancellation circuitry configured to modify the frequency-domain receive symbol based on at least one frequency-domain transmit symbol and a frequency-domain crosstalk channel estimate of a crosstalk channel between the transmitter and the receiver; and
a processor communicatively coupled to the transceiver and configured to perform primary processing operations of the device.
11. The mobile device of claim 10 , wherein the transformation circuitry is configured to transform the frequency-domain transmit symbol from frequency domain to time domain via one of an inverse Fourier transform, an inverse Wavelet transform, an inverse Laplace transform, an inverse Cosine transform, or a Filter bank, and
wherein the inverse transformation circuitry is configured to transform the time-domain transmit signal from time domain to frequency domain based on one of a Fourier transform, a Wavelet transform, a Laplace transform, an Cosine transform, or a Filter bank.
12. The mobile device of claim 10 , wherein the transceiver is a multicarrier transceiver, wherein a carrier frequency of a multicarrier time-domain transmit signal and a carrier frequency of a multicarrier time-domain receive signal are shifted by a frequency shift Δf, and
wherein the self-interference cancellation circuitry is configured to compute a crosstalk from a multicarrier transmit signal subcarrier n to a multicarrier receive signal subcarrier m based on a distance between the subcarriers n, m and based on the frequency shift Δf.
13. The mobile device of claim 10 , wherein a transmit carrier frequency and a receive carrier frequency are shifted by a frequency shift Δf and a timing of a multicarrier transmit signal is shifted vis-à-vis a multicarrier receive signal by a time shift Δt, wherein the self-interference cancellation circuitry is configured to compute a crosstalk from a subcarrier n of the multicarrier transmit signal to a subcarrier m of the multicarrier receive signal based on a distance between the subcarriers n, m, the frequency shift Δf, and the time shift Δt.
14. The mobile device of claim 10 , wherein the transceiver is an OFDM transceiver, wherein the self-interference cancellation circuitry is configured to compute the crosstalk from the OFDM transmit signal to the OFDM receive signal based on
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-
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2
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denoting a normalized length of a temporal overlap between the OFDM transmit symbol and the OFDM receive symbol.
15. The mobile device of claim 10 , wherein the self-interference cancellation circuitry is configured to estimate the frequency-domain crosstalk channel estimate based on a transmission of pilot symbols.
16. A base station comprising:
a transmitter comprising transformation circuitry configured to transform a frequency-domain transmit symbol from frequency domain to time domain to generate a time-domain transmit signal;
a receiver comprising inverse transformation circuitry configured to transform a time-domain receive signal from time domain to frequency domain to generate a frequency-domain receive symbol; and
self-interference cancellation circuitry configured to modify the frequency-domain receive symbol based on at least one frequency-domain transmit symbol and a frequency-domain crosstalk channel estimate of a crosstalk channel between the transmitter and the receiver.
17. The base station of claim 16 , the transformation circuitry is configured to transform the frequency-domain transmit symbol from frequency domain to time domain via one of an inverse Fourier transform, an inverse Wavelet transform, an inverse Laplace transform, an inverse Cosine transform, or a Filter bank, and
wherein the inverse transformation circuitry is configured to transform the time-domain transmit signal from time domain to frequency domain based on one of a Fourier transform, a Wavelet transform, a Laplace transform, an Cosine transform, or a Filter bank.
18. The base station of claim 16 , wherein a carrier frequency of a multicarrier time-domain transmit signal and a carrier frequency of a multicarrier time-domain receive signal are shifted by a frequency shift Δf, and
wherein the self-interference cancellation circuitry is configured to compute a crosstalk from a multicarrier transmit signal subcarrier n to a multicarrier receive signal subcarrier m based on a distance between the subcarriers n, m and based on the frequency shift Δf.
19. The base station of claim 16 , wherein a transmit carrier frequency and a receive carrier frequency are shifted by a frequency shift Δf and a timing of a multicarrier transmit signal is shifted vis-à-vis a multicarrier receive signal by a time shift Δt, wherein the self-interference cancellation circuitry is configured to compute a crosstalk from a subcarrier n of the multicarrier transmit signal to a subcarrier m of the multicarrier receive signal based on a distance between the subcarriers n, m, the frequency shift Δf, and the time shift Δt.
20. The base station of claim 16 , wherein the self-interference cancellation circuitry is configured to estimate the frequency-domain crosstalk channel estimate based on a transmission of pilot symbols.