Equalization and estimation processing in wireless devices
Millimeter-wave (mmWave) and sub-mmWave technology, apparatuses, and methods that relate to transceivers and receivers for wireless communications are described. The various aspects include an apparatus of a communication device including one or more antennas configured to receive an RF signal and an ADC system. The ADC system includes a 1-bit ADC configured to receive the RF signal, and an ADC controller circuitry configured to measure a number of positive samples in the received RF signal for a plurality of thresholds of the 1-bit ADC, estimate receive signal power associated with the received RF signal based on the measured number of positive samples, determine a direct current (DC) offset in the received RF signal using the estimated received signal power, and adjust the received RF signal based on the determined DC offset.
1. An apparatus of a communication device, the apparatus comprising:
a receiver comprising:
equalization circuitry configured to receive a filtered radio frequency (RF) signal and generate an equalized RF signal;
non-linearity compensation circuitry configured to apply a non-linear feature set to the equalized RF signal to generate a compensated signal, the non-linear feature set including a plurality of weights; and
closed-loop training circuitry configured to:
compare, in a digital domain of the receiver, a plurality of signal constellation points corresponding to the compensated signal with a plurality of training samples to determine an error signal associated with the plurality of signal constellation points, the plurality of training samples generated internally within the receiver; and
adjust the plurality of weights of the non-linear feature set based on the determined error signal.
2. The apparatus of claim 1 , the receiver further comprising:
slicer circuitry coupled to the closed-loop training circuitry, the slicer configured to generate the plurality of signal constellation points based on the compensated signal.
3. The apparatus of claim 2 , the receiver further comprising:
second equalization circuitry coupled to an output of the non-linearity compensation circuitry via an adder;
wherein the second equalization circuitry receives a plurality of prior signal constellation points from the slicer circuitry and generates a filtered representation of the prior signal constellation points; and
wherein the adder is configured to generate a differential signal between the compensated signal and the filtered representation of the prior signal constellation points.
4. The apparatus of claim 3 , wherein the slicer generates the plurality of signal constellation points using the differential signal.
5. The apparatus of claim 3 , wherein the equalization circuitry is a feed forward equalizer (FFE) circuit and the second equalization circuitry is a decision feedback equalizer (DFE) circuit.
6. The apparatus of claim 2 , wherein the receiver is configured to operate in one of a training mode and a data processing mode, and wherein during the training mode, the closed-loop training circuitry is configured to:
receive the plurality of training samples from a training signal generator; and
determine the error signal using a quantized representation of a differential signal corresponding to the plurality of training samples.
7. The apparatus of claim 6 , the receiver further comprising:
a 1-bit analog-to-digital-converter (ADC) circuit configured to receive the differential signal corresponding to the plurality of training samples and generate the quantized representation.
8. The apparatus of claim 6 , wherein the receiver comprises:
a demodulator coupled to the slicer circuitry, the demodulator configured to generate, during the data processing mode, a demodulated binary signal corresponding to the filtered RF signal based on the plurality of signal constellation points.
9. The apparatus of claim 6 , wherein during the data processing mode, the closed-loop training circuitry is configured to:
receive a quantized representation of a differential signal corresponding to the compensated signal;
determine, in the digital domain of the receiver, the error signal using the quantized representation of the differential signal corresponding to the compensated signal and a plurality of signal constellation points associated with the differential signal corresponding to the compensated signal; and
adjust the plurality of weights of the non-linear feature set based on the determined error signal.
10. The apparatus of claim 6 , wherein during the data processing mode, the closed-loop training circuitry is configured to:
receive a representation of a differential signal corresponding to the compensated signal;
determine, in an analog domain of the receiver, the error signal using the representation of the differential signal corresponding to the compensated signal and a plurality of signal constellation points associated with the differential signal corresponding to the compensated signal; and
adjust the plurality of weights of the non-linear feature set based on the determined error signal.
11. An method of a communication device, the method comprising:
receiving a filtered radio frequency (RF) signal at a receiver;
generating an equalized RF signal based on the filtered RF signal;
applying a non-linear feature set to the equalized RF signal to generate a compensated signal, the non-linear feature set including a plurality of weights;
comparing a plurality of signal constellation points corresponding to the compensated signal with a plurality of training samples to determine an error signal associated with the plurality of signal constellation points, the plurality of training samples generated internally within the receiver; and
adjusting the plurality of weights of the non-linear feature set based on the determined error signal.
12. The method of claim 11 , further comprising:
generating the plurality of signal constellation points based on the compensated signal.
13. The method of claim 12 , further comprising:
receiving a plurality of prior signal constellation points from slicer circuitry;
generating a filtered representation of the prior signal constellation points; and
generating a differential signal between the compensated signal and the filtered representation of the prior signal constellation points.
14. The method of claim 13 , further comprising:
generating the plurality of signal constellation points using the differential signal.
15. The method of claim 12 , further comprising:
receiving the plurality of training samples from a training signal generator.
16. The method of claim 15 , further comprising:
determining the error signal using a quantized representation of a differential signal corresponding to the plurality of training samples.
17. The method of claim 16 , further comprising:
receiving the differential signal corresponding to the plurality of training samples and generate the quantized representation.
18. The method of claim 15 , further comprising:
generating a demodulated binary signal corresponding to the filtered RF signal based on the plurality of signal constellation points.
19. The method of claim 15 , further comprising:
receiving a quantized representation of a differential signal corresponding to the compensated signal;
determining the error signal using the quantized representation of the differential signal corresponding to the compensated signal and a plurality of signal constellation points associated with the differential signal corresponding to the compensated signal; and
adjusting the plurality of weights of the non-linear feature set based on the determined error signal.
20. The method of claim 15 , further comprising:
receiving a representation of a differential signal corresponding to the compensated signal;
determining the error signal using the representation of the differential signal corresponding to the compensated signal and a plurality of signal constellation points associated with the differential signal corresponding to the compensated signal; and
adjusting the plurality of weights of the non-linear feature set based on the determined error signal.
21. An apparatus comprising:
means for receiving a filtered radio frequency (RF) signal;
means for generating an equalized RF signal based on the filtered RF signal;
means for applying a non-linear feature set to the equalized RF signal to generate a compensated signal, the non-linear feature set including a plurality of weights;
means for comparing a plurality of signal constellation points corresponding to the compensated signal with a plurality of training samples to determine an error signal associated with the plurality of signal constellation points, the plurality of training samples generated internally within the means for receiving; and
means for adjusting the plurality of weights of the non-linear feature set based on the determined error signal.
22. The apparatus of claim 21 , further comprising:
means for generating the plurality of signal constellation points based on the compensated signal.
23. The apparatus of claim 22 , further comprising:
means for receiving a plurality of prior signal constellation points from slicer circuitry;
means for generating a filtered representation of the prior signal constellation points; and
means for generating a differential signal between the compensated signal and the filtered representation of the prior signal constellation points.
24. The apparatus of claim 23 , further comprising:
means for generating the plurality of signal constellation points using the differential signal.