Method and system of channel estimation
AssigneeTelefonaktiebolaget LM Ericsson (publ)
InventorJiann-Ching Guey
Life of this patent
Estimating the term…
Abstract
Channel estimation is performed using side information. A signal transmitted over a radio channel includes side information corresponding to a first predetermined signal and a second predetermined signal. The first predetermined signal is different from the second predetermined signal. An estimate of the radio channel is determined using both the first predetermined signal and the second predetermined signal. Using multiple sources of side information improves the accuracy and the efficiency of the channel estimation. One example application is Orthogonal Frequency Division Multiplexing based communications systems.
Claims23
A method of channel estimation as applied to a DS-CDMA radio communications system that uses OFDM, comprising:
- a radio receiver initializing radio channel specific parameters and receiving a signal transmitted over a radio channel including a first predetermined signal of a first type that includes direct sequence pilot chips and a second predetermined signal of a second type that includes OFDM pilot symbols on OFDM sub-carriers, the first type of predetermined signal being different from the second type of predetermined signal, and
- a processor determining an estimate of the radio channel according to an objective function that minimizes residual error between an actual representation of the radio channel and the estimate of the radio channel determined based on both the OFDM pilot symbols on OFDM sub-carriers and the direct sequence pilot chips.
A method of channel estimation, comprising:
- a radio receiver receiving a signal transmitted over a radio channel including a first predetermined signal of a first type and a second predetermined signal of a second type, the first type of predetermined signal being different from the second type of predetermined signal, and
- a processor determining an estimate of the radio channel using both the first predetermined signal of the first type and the second predetermined signal of the second type,
- wherein determining the estimate of the radio channel includes:
- calculating a first channel estimate using the first predetermined signal;
- determining a first accuracy of the first channel estimate;
- and
- calculating a second channel estimate using the first channel estimate, the first accuracy of the first channel estimate and the second predetermined signal.
Apparatus for channel estimation as applied to a DS-CDMA radio receiving node configured to use OFDM, comprising:
- a receiver for receiving a signal transmitted over a radio channel including a first predetermined signal that includes direct sequence pilot chips and a second predetermined signal that includes OFDM pilot symbols on OFDM sub-carriers, the first predetermined signal being different from the second predetermined signal, and
- a processor for determining an estimate of the radio channel according to an objective function that minimizes residual error between an actual representation of the radio channel and the estimate of the radio channel determined based on both the OFDM pilot symbols on OFDM sub-carriers and the direct sequence pilot chips.
Apparatus for channel estimation, comprising:
- a receiver for receiving a signal transmitted over a radio channel including a first predetermined signal and a second predetermined signal the first predetermined signal being different from the second predetermined signal, and
- a processor for determining an estimate of the radio channel using both the first predetermined signal and the second predetermined signal,
- wherein the processor is configured to;
- calculate a first channel estimate using the first predetermined signal;
- determine a first accuracy of the first channel estimate;
- calculate a second channel estimate using the first channel estimate, the first accuracy of the first channel estimate and the second predetermined signal.
A radio communications system, comprising:
- a transmitter for transmitting a signal over a radio channel including a first predetermined signal and a second predetermined signal, the first predetermined signal being different from the second predetermined signal, and
- a receiver for receiving the signal transmitted over a radio channel, the receiver including:
- a processor for determining an estimate of the radio channel using both the first predetermined signal and the second predetermined signal, the processor being configured to:
- calculate a first channel estimate using the first predetermined signal;
- determine a first accuracy of the first channel estimate;
- and
- calculate a second channel estimate using the first channel estimate, the first accuracy of the first channel estimate and the second predetermined signal.
Dependencies are inferred from the claim text.