Methods and devices for channel estimation and OFDM receiver

A processing circuit, comprising:

• a receiving port configured to receive a receive symbol comprising:
• a plurality of interfering transmissions from:
• a first transmit symbol, the first transmit symbol comprising a plurality of unknown modulated symbols interleaved with a plurality of known modulated symbols;
• and
• a second transmit symbol, the second transmit symbol comprising a plurality of unknown modulated symbols interleaved with a plurality of known modulated symbols,
• wherein the plurality of interfering transmissions from the first transmit symbol and the second transmit symbol are a plurality of transmissions of different time instances;
• and
• a channel estimator configured to estimate a channel based on the receive symbol and a plurality of estimates of the first transmit symbol and the second transmit symbol, wherein the channel estimator is configured to estimate the channel based on a signal representation comprising a dictionary matrix, wherein the dictionary matrix comprises the first transmit symbol and the second transmit symbol, and the estimating comprises jointly estimating the channel and the first and second transmit symbols by applying the signal representation.

An OFDM receiver, comprising:

• a receiving port configured to receive a receive OFDM symbol comprising:
• a plurality of interfering transmissions from a first OFDM symbol, the first OFDM symbol comprising a plurality of unknown modulated symbols interleaved with a plurality of known modulated symbols;
• and
• a second OFDM symbol, the second OFDM symbol comprising a plurality of unknown modulated symbols interleaved with a plurality of known modulated symbols,
• wherein the plurality of interfering transmissions from the first OFDM symbol and the second OFDM symbol are a plurality of transmissions of different time instances;
• a channel estimator configured to estimate a plurality of soft estimates of a channel impulse response and of a noise power based on the receive OFDM symbol and based on a plurality of soft estimates of the first OFDM symbol and the second OFDM symbol, wherein the channel estimator is configured to estimate the plurality of soft estimates of the channel based on a signal representation comprising a dictionary matrix, wherein the dictionary matrix comprises the first OFDM symbol and the second OFDM symbol, and the estimating comprises jointly estimating the channel and the first and second transmit symbols by applying the signal representation;
• and
• an equalizer configured to estimate the plurality of soft estimates of the first OFDM symbol and the second OFDM symbol based on the plurality of soft estimates of the channel impulse response and the noise power estimated by the channel estimator.