Channel estimation using precoded reference symbols

A decoder for a terminal of a cellular telecommunication system in which broadcasted system information is provided from at least one cell operated by a network node of the telecommunication system, where the telecommunication system employs Orthogonal Frequency Division Multiple Access, the decoder comprising:

• a receiver arranged to receive a transmission signal comprising reference symbols and synchronisation symbols from the network node of the at least one cell;
• a pre-coding vector determinator arranged to determine at least one pre-coding vector, of which one pre-coding vector being associated with transmission by at least one transmit antenna of the network node of the at least one cell, for the transmission signal;
• and
• a channel estimator arranged to estimate, for each of the at least one pre-coding vector, a channel estimate for all sub-carriers of the received transmission signal from the received reference symbols and a reference symbol channel model defined by reference symbols of the transmission signal, and from the synchronisation symbols, the at least one pre-coding vector and a synchronisation symbol channel model defined by synchronisation symbols of the transmission signal, wherein the channel estimate is Ĥ=KY, when Ĥ is biased, where Y are received symbols and
• K
• =
• [
• I
• ⁢
• ⁢
• A
• H
• ]
• ·
• (
• [
• I
• A
• ]
• ⁡
• [
• I
• ⁢
• ⁢
• A
• H
• ]
• +
• ∑
• E
• )
• -
• 1
• where I is an identity matrix, A is the pre-coding vector, and ΣE is the noise covariance matrix.

A user equipment (UE) of a cellular telecommunication system, the telecommunication system enabling determination of broadcasted system information by the UE from broadcasted information from at least one cell operated by a network node of the telecommunication system, where the telecommunication system employs Orthogonal Frequency Division Multiple Access, the UE comprising:

• at least one processor;
• and
• a non-transitory computer-readable storage medium, coupled to the at least one processor, including computer-readable instructions, when executed by the at least one processor, are configured to:
• receive a transmission signal, comprising reference symbols and synchronization symbols, from the network node of the at least one cell;
• determine at least one pre-coding vector, of which one pre-coding vector being associated with transmission by an at least one transmit antenna of the network node of the at least one cell, for the transmission signal;
• and
• estimate, for each of the at least one pre-coding vector, a channel estimate for all sub-carriers of the received transmission signal from the received reference symbols and a reference symbol channel model defined by reference symbols of the transmission signal, and from the synchronization symbols, the at least one pre-coding vector and a synchronization symbol channel model defined by synchronization symbols of the transmission signal, wherein the channel estimate is Ĥ=KY, when Ĥ is biased, where Y are received symbols and
• K
• =
• [
• I
• ⁢
• ⁢
• A
• H
• ]
• ·
• (
• [
• I
• A
• ]
• ⁡
• [
• I
• ⁢
• ⁢
• A
• H
• ]
• +
• ∑
• E
• )
• -
• 1
• where I is an identity matrix, A is the pre-coding vector, and ΣE is the noise covariance matrix.