Multiple antenna receiver system and method
View Patent ↗A technique for processing received signals in multiple-antenna systems. Received signals from the different antennas may be amplified by a Low Noise Amplifier (LNA) and time-multiplexed by a switch to form a single analog signal. The time-multiplexed analog signal is down-converted and processed using a single RF chain for each signal component. This may result in an N-fold decrease in hardware in multiple antenna receiver systems.
1. An apparatus for processing signals received on a multiple antenna receiver system (MARS), comprising:
a plurality of antennas;
a switch coupled to the plurality of antennas for switchable coupling to each selected one of the plurality of antennas in sequence, to form a single analog signal with discrete sequential samples from each of the antennae;
an analog-to-digital converter (ADC) coupled to the switch;
a switch synchronization and control block coupled to both the switch and to the ADC to synchronize the operation of the switch and the ADC such that the ADC converts the single analog signal from the switch to sampled digital signals from each antennae; and
a digital signal processing (DSP) block, coupled to the ADC, for processing the sampled digital signals from each antenna to remove inter-antenna symbol interference (IASI) and inter-symbol interference (ISI), and wherein the DSP block includes:
an equalizer to filter the signals received from the antennas into filtered signals;
a multiple antenna processing module; and
a demodulator for applying a technique selected from the group of techniques consisting of orthogonal frequency division multiplexing (OFDM), direct sequence spread spectrum (DSSS), complementary code keying (CCK).
2. The apparatus of claim 1 , wherein the equalizer removes IASI interference from the filtered signal.
3. The apparatus of claim 1 , wherein the multiple antenna processing module includes one or more modules selected from the group consisting of a space-time decoder, a diversity combining module, and a beamforming module.
4. The apparatus of claim 1 wherein the equalizer and the multiple antenna processing module perform tasks sequentially or jointly.
5. A method for processing signals received on a multiple antenna receiver system (MARS), comprising:
providing a plurality of antennas;
switchably coupling to each one the plurality of antennas in sequence to form a single analog signal with discrete sequential samples from each of the antenna;
synchronously converting from analog-to-digital the single analog signal from the switchably coupling act into corresponding discrete digital signals from each antennae;
receiving digitized I-signal and Q-signal components, of the digital signals from each antenna converted in the converting act;
recovering the timing, phase, and frequency associated with the received I-signal and Q-signal components;
equalizing the I-signal and Q-signal components to compensate for inter-antenna symbol interference (IASI) and inter-symbol interference (ISI); and
space-time processing the I-signal and Q-signal to reproduce the plurality of signals received from the plurality of antennas.