Channel tracking and transmit beamforming with frugal feedback

A method comprising:

• receiving, by a receiving device and through a wireless communication channel, a pilot signal transmitted by a transmitting device having a plurality of antennas;
• determining, by the receiving device and based on the received pilot signal, channel state feedback comprising a quantized representation of the pilot signal as received by the receiving device;
• and
• sending, by the receiving device and through the wireless communication channel, the channel state feedback to the transmitting device.

A transmission device comprising:

• multiple antennas for sending and receiving communication information;
• a memory for storing the communication information;
• one or more processors for processing the communication information, wherein the one or more processors are configured to:
• send, through a wireless communication channel and using the multiple antennas, a pilot signal in accordance with a first set of transmission parameters, wherein the first set of transmission parameters is determined based on a first estimated state of the channel;
• receive, using one or more of the multiple antennas, channel state feedback from a receiving device, wherein the channel state feedback comprises a quantized representation of the pilot signal as received by the receiving device;
• determine, based on the channel state feedback, an updated estimated state of the wireless communication channel;
• and
• send, via the wireless communication channel and using the multiple antennas, one or more data symbols in accordance with a second set of transmission parameters, wherein the second set of transmission parameters is determined based on the updated estimated state of the channel.

A receiving device comprising:

• a plurality of receive antennas for receiving communication information;
• a memory for storing the communication information;
• and
• one or more processors for processing the communication information, wherein the one or more processors are configured to:
• receive, through a wireless communication channel, a pilot signal transmitted by a transmitting device;
• determine, based on the received pilot signal, channel state feedback comprising a quantized representation of the pilot signal as received at the receiving device;
• and
• send, through the wireless communication channel, the channel state feedback to the transmitting device.

A method comprising:

• applying, at both a transmitter and a receiver separated by a wireless communication channel, a Kalman filter to track a state of the communication channel;
• periodically sending, by the receiving device, a quantization of a sign of innovation (SOI) of a pilot signal from the transmitter as received by the receiver;
• updating, with the transmitter, the Kalman filter at the transmitter based on the quantized SOI received from the receiver;
• and
• beamforming and outputting by the transmitter, based on the Kalman filter of the transmitter, a transmission through the communication channel to the receiver.