Multi-mode receiver with adaptive mode selection
View Patent ↗Receivers and methods are provided that include multiple modes of processing signals from multiple antennas. These include legacy, SAIC (single antenna interference cancellation) and MSRD. Various methods are provided for selecting an appropriate receiver processing function. These include looking at correlation and gain imbalance between antennas, looking at the processing gain resulting from one or more of the receiver processing functions, and looking at the equalization quality of at least two receiver processing functions.
1. A receiver comprising:
at least two antennas;
a plurality of receiver processing functions comprising at least one receiver processing function for processing a single signal and at least one receiver processing function for processing at least two signals; and
a branch power detector operable to determine a power of each signal received by each antenna and compare the power of each signal with the power of each other signal to determine a measure of imbalance in the powers of the signals;
wherein the receiver is operable to select a receiver processing function by taking into account the measure of imbalance in the powers of the signals when compared to a threshold; and
the receiver is further operable to select the receiver processing function by de-selecting a receiver processing function of said plurality of receiver processing functions as a function of processing gain for the de-selected receiver processing function.
2. The receiver of claim 1 wherein the receiver is operable to select the receiver processing function by de-selecting at least one of the receiver processing functions when the measure of imbalance is above a threshold.
3. The receiver of claim 1 wherein the plurality of receiver processing functions comprise at least three receiver processing functions, and wherein the receiver is further operable to select the receiver processing function by de-selecting at least one receiver processing function as a function of modulation type, and selecting between remaining receiver processing functions.
4. The receiver of claim 1 wherein:
the receiver is further operable to select the receiver processing function by selecting between first and second receiver processing functions of said plurality of receiver processing functions as a function of modulation type by:
selecting the first receiver processing function when the modulation type is 8-PSK; and
selecting the second receiver processing function when the modulation type is GMSK.
5. The receiver of claim 1 wherein:
the receiver is further operable to select the receiver processing function by de-selecting a receiver processing function of said plurality of receiver processing functions as a function of processing gain for the de-selected receiver processing function by:
determining a processing gain for one of a first and second receiver processing functions of said plurality of processing functions; and
de-selecting the one of the first and second receiver processing functions if the determined processing gain is below a threshold.
6. The receiver of claim 1 further operable to select the receiver processing function by:
performing receiver processing using at least two of the receiver processing functions;
performing a respective equalization on an output of each of the at least two receiver processing functions to produce a respective equalized output; and
determining a quality metric for each equalized output;
selecting the receiver processing function according to the quality metrics.
7. A method comprising:
receiving a respective signal on each of at least two antennas;
determining a power of each signal and comparing the power of each signal with the power of each other signal to determine a measure of imbalance in the powers of the signals;
selecting a receiver processing function of a plurality of receiver processing functions comprising at least one receiver processing function for processing a single signal and at least one receiver processing function for processing at least two signals by taking into account the measure of imbalance in the powers of the signals when compared to a threshold; and
producing an output using the selected receiver processing function;
wherein selecting the receiver processing function further comprises:
executing one of the plurality of receiver processing functions and determining a processing gain achieved by the receiver processing function; and
selecting the receiver processing function by de-selecting a receiver processing function of said plurality of receiver processing functions as a function of processing gain for the de-selected receiver processing function.
8. The method of claim 7 wherein selecting the receiver processing function further comprises:
performing receiver processing using at least two of the receiver processing functions;
performing a respective equalization on an output of each of the at least two receiver processing functions to produce a respective equalized output; and
determining a quality metric for each equalized output;
selecting the selected receiver processing function according to the quality metrics.
9. A receiver comprising:
at least two antennas;
a plurality of receiver processing functions comprising at least one receiver processing function for processing a single signal and at least one receiver processing function for processing at least two signals; and
a correlation detector operable to determine a correlation between signals received on the at least two antennas;
wherein the receiver is operable to select a receiver processing function by taking into account the correlation when compared to a threshold; and
the receiver is further operable to select the receiver processing function by de-selecting a receiver processing function of said plurality of receiver processing functions as a function of processing gain for the de-selected receiver processing function.
10. The receiver of claim 9 wherein the plurality of receiver processing functions comprise at least three receiver processing functions, and wherein the receiver is operable to select the receiver processing functions by de-selecting at least one of the receiver processing functions when the correlation is above a threshold, and selecting between remaining receiver processing functions.
11. The receiver of claim 9 wherein the plurality of receiver processing functions comprise at least three receiver processing functions, and wherein the receiver is further operable to select the receiver processing function by de-selecting at least one receiver processing function as a function of modulation type, and selecting between remaining receiver processing functions.
12. The receiver of claim 9 wherein:
the receiver is further operable to select the receiver processing function by selecting between first and second receiver processing functions of said plurality of receiver processing functions as a function of modulation type by:
selecting the first receiver processing function when the modulation type is 8-PSK; and
selecting the second receiver processing function when the modulation type is GMSK.
13. The receiver of claim 9 wherein:
the receiver is further operable to select the receiver processing function by de-selecting a receiver processing function of said plurality of receiver processing functions as a function of processing gain for the de-selected receiver processing function by:
determining a processing gain for one of a first and second receiver processing functions of said plurality of processing functions; and
de-selecting the one of the first and second receiver processing functions if the determined processing gain is below a threshold.
14. The receiver of claim 9 further operable to select the receiver processing function by:
performing receiver processing using at least two of the receiver processing functions;
performing a respective equalization on an output of each of the at least two receiver processing functions to produce a respective equalized output; and
determining a quality metric for each equalized output;
selecting the receiver processing function according to the quality metrics.
15. A method comprising:
receiving a respective signal on each of at least two antennas;
determining a correlation between the signals;
selecting a receiver processing function of a plurality of receiver processing functions comprising at least one receiver processing function for processing a single signal and at least one receiver processing function for processing at least two signals by taking into account the correlation when compared to a threshold; and
producing an output using the selected receiver processing function;
wherein selecting the receiver processing function further comprises:
executing one of the plurality of receiver processing functions and determining a processing gain achieved by the receiver processing function;
selecting the receiver processing function by de-selecting a receiver processing function of said plurality of receiver processing functions as a function of processing gain for the de-selected receiver processing function.
16. The method of claim 15 wherein selecting the receiver processing function further comprises:
performing receiver processing using at least two of the receiver processing functions;
performing a respective equalization on an output of each of the at least two receiver processing functions to produce a respective equalized output; and
determining a quality metric for each equalized output;
selecting the selected receiver processing function according to the quality metrics.