Groupwise successive interference cancellation for block transmission with reception diversity
View Patent ↗A plurality of data signals are received over an antenna array having a plurality of antenna elements. The data signals are transmitted over a shared spectrum in a wireless communication system. A signal having each of the data signals is received over each antenna element. The plurality of data signals are grouped into a plurality of groups. The received signals of the antenna elements are matched filtered for a first group of the plurality of groups, producing a matched filtered result. Data is jointly detected of the first group using the matched filtered result. An interference correction signal is constructed using the detected data for each antenna element. The interference cancelled result is subtracted from the received signal of each antenna element, producing an interference cancelled result for each antenna element. Data is successively detected for remaining groups using the interference cancelled result for each antenna element.
1. An apparatus for transmitting and receiving a plurality of data signals using an antenna array, the apparatus comprising:
a transmitter configured to transmit a plurality of data signals over a shared spectrum;
a receiver configured to receive a radio frequency (RF) signal, the receiver comprising:
an antenna array having a plurality of antenna elements,
a plurality of demodulators,
a channel estimation device configured to provide channel information,
a group wise successive interference cancellation joint detection device (GSJC-JD), for estimating the transmitted reference data signals as either hard or soft symbols, configured to:
group the plurality of transmitted data signals into a plurality of groups,
match filter the plurality of transmitted data signals of the antenna array for a first group of the plurality of groups, producing a match filtered result,
jointly detect data of the first group using the match filtered result,
construct an interference correction signal using the detected data for each antenna element,
subtract the received signal of each antenna element the interference correction signal for that element, producing an interference cancelled result for each antenna element,
successively detect data of remaining groups using the interference cancelled result for each antenna element, wherein the jointly detecting data produces soft symbols, and
convert the produced soft symbols into hard symbols prior to the interference correction signal construction.
2. The apparatus of claim 1 wherein the transmitter further comprises:
a data generator configured to generate reference data signals to communicate over a reference channel;
a spreading and modulation device configured to generate reference data into a communication burst;
a modulator configured to modulate the communication burst into a radio frequency (RF) signal; and
an antenna configured to radiate the RF signal through a wireless radio channel to a receiver.
3. The apparatus of claim 1 wherein:
each of the plurality of demodulators corresponds to one of the plurality of antenna elements; and
each demodulator is configured to demodulate the RF signal received by the corresponding one of the plurality of antenna elements to produce baseband signals.
4. The apparatus of claim 1 wherein the channel estimation device is configured to provide channel information based on training sequences components in the baseband signals.
5. The apparatus of claim 2 wherein the communication burst is time multiplexed with a training sequence in appropriate assigned time slots and codes.
6. The apparatus of claim 5 wherein the communication burst includes:
a midamble;
a guard period; and
two data fields.
7. The apparatus of claim 6 wherein the midamble is between the two data fields.
8. The apparatus of claim 6 wherein the guard period separates the communication burst from a next communication burst.
9. The apparatus of claim 6 wherein the two data fields are the same length.
10. The apparatus of claim 2 wherein the communication burst is an almost continuous global pilot.
11. The apparatus of claim 2 wherein the modulator is configured to use direct phase shift keying (DPSK).
12. The apparatus of claim 2 wherein the modulator is configured to use quadrature phase shift keying (QPSK).
13. The apparatus of claim 2 wherein the modulator is configured to use M-ary quadrature amplitude modulation (QAM).