Interference cancellation in a transceiver device
The present disclosure is directed to improvements in interference mitigation for Adjacent Channel Leakage in wireline communication, and more specifically, but not exclusively, to improved kernel designs that can facilitate interference mitigation for Adjacent Channel Leakage in cable modem systems. Examples of the present disclosure provide an apparatus for a transceiver device that comprises interference cancellation circuitry configured to cancel interference caused by upstream signals in one or more upstream sub-bands on one or more downstream sub-bands based on a combination of a plurality of kernels. The interference is at least partially caused by non-linearities within a transmission circuitry of the transceiver device, the plurality of kernels representing the non-linearities within the transmission circuitry of the transceiver device. Each of the kernels comprises one or more associated terms, with each of the associated terms being in-band for at least one of the one or more downstream sub-bands.
1. An apparatus for a transceiver device, comprising:
interference cancellation circuitry configured to cancel interference caused by upstream signals in one or more upstream sub-bands on one or more downstream sub-bands based on a combination of a plurality of kernels,
wherein the interference is at least partially caused by non-linearities within a trans-mission circuitry of the transceiver device, the plurality of kernels representing the non-linearities within the transmission circuitry of the transceiver device,
wherein each of the kernels comprises one or more associated terms, with each of the associated terms being in-band for at least one of the one or more downstream sub-bands.
2. The apparatus according to claim 1 , wherein the interference cancellation circuitry is configured to cancel the interference caused by signals in two or more upstream sub-bands, wherein each of the two or more upstream sub-bands is represented separately within the kernels.
3. The apparatus according to claim 1 , wherein the interference cancellation circuitry is configured to generate an estimated interference signal caused by the upstream signals using the plurality of kernels, and to cancel the interference based on the estimated interference signal.
4. The apparatus according to claim 3 , wherein the interference cancellation circuitry is configured to cancel the interference within a downstream signal received by the transceiver device based on the estimated interference signal.
5. The apparatus according to claim 4 , wherein the interference cancellation circuitry is configured to cancel the interference within the downstream signal by subtracting the estimated interference signal from the downstream signal.
6. The apparatus according to claim 3 , wherein the interference cancellation circuitry is configured to upsample the upstream signals to an upsampling frequency, and to generate the estimated interference signal based on the upsampled upstream signals.
7. The apparatus according to claim 6 , wherein the upsampling frequency is a multiple of a bandwidth of a single sub-band of the one or more upstream sub-bands.
8. The apparatus according to claim 7 , wherein the plurality of kernels comprise kernels of different order, wherein the upsampling frequency is at least the bandwidth of the single sub-band of the one or more upstream sub-bands multiplied by the order of the kernel with the highest order.
9. The apparatus according to claim 1 , wherein the plurality of kernels comprise kernels of different order, wherein each kernel is based on
φ k ( t )= x ( t )| x ( t )| k-1
where k is the order of the kernel, φ k (t) is the kernel of order k, and wherein a term of the kernels that is out-of-band of the one or more downstream sub-bands is omitted from the respective kernel.
10. The apparatus according to claim 1 , wherein the interference cancellation circuitry is configured to cancel the interference caused by signals in a first upstream sub-band f 1 and in a second upstream sub-band f 2 , wherein
x ( t )= x 1 ( t ) e j2πf 1 t +x 2 ( t ) e j2πf 2 t
where x 1 (t) and x 2 (t) are the respective sub-terms for the first upstream sub-band f 1 and the second upstream sub-band f 2 .
11. The apparatus according to claim 1 , wherein the plurality of kernels comprise kernels of different order, wherein the highest order is at least 3 and/or at most 10.
12. The apparatus according to claim 1 , wherein the interference cancellation circuitry is configured to cancel the interference based on a weighted combination of the plurality of kernels.
13. The apparatus according to claim 12 , wherein the interference cancellation circuitry is configured to adapt the weights of the weighted combination.
14. The apparatus according to claim 1 , wherein the interference cancellation circuitry is configured to cancel the interference caused by signals in two or more upstream sub-bands, wherein the two or more upstream sub-bands and the one or more down-stream sub-band are a plurality of adjacent sub-bands of a bandwidth.
15. The apparatus according to claim 14 , wherein the two or more upstream sub-bands are adjacent to one another.
16. The apparatus according to claim 14 , wherein at least one of the one or more down-stream sub-bands is between two of the two or more upstream sub-bands.
17. A transceiver device comprising the apparatus according to claim 1 , transmission circuitry and receive circuitry, wherein the transceiver device is configured to receive a downstream signal via the receive circuitry, and to perform interference cancellation on the received downstream signal using the interference cancellation circuitry.
18. A cable modem comprising the apparatus according to claim 1 , wherein the cable modem is the transceiver device.
19. A device for a transceiver device, comprising:
means for cancelling interference configured to cancel interference caused by upstream signals in one or more upstream sub-bands on one or more downstream sub-bands based on a combination of a plurality of kernels,
wherein the interference is at least partially caused by non-linearities within a trans-mission circuitry of the transceiver device, the plurality of kernels representing the non-linearities within the transmission circuitry of the transceiver device,
wherein each of the kernels comprises one or more associated terms, with each of the associated terms being in-band for at least one of the one or more downstream sub-bands.
20. A transceiver device comprising the device according to claim 19 , means for transmitting and means for receiving, wherein the transceiver device is configured to receive a downstream signal via the receive circuitry, and to perform interference cancellation on the received downstream signal using the means for can-celling interference.
21. A method for a transceiver device, comprising:
cancelling interference caused by upstream signals in one or more upstream sub-bands on one or more downstream sub-bands based on a combination of a plurality of kernels,
wherein the interference is at least partially caused by non-linearities within a transmission circuitry of the transceiver device, the plurality of kernels representing the non-linearities within the transmission circuitry of the transceiver device,
wherein each of the kernels comprises one or more associated terms, with each of the associated terms being in-band for at least one of the one or more downstream sub-bands.