Doppler estimator for OFDM systems
AssigneeMaxLinear, Inc.
InventorSridhar Ramesh
Life of this patent
Estimating the term…
Abstract
A method of estimating the Doppler spread of a communication channel includes computing a first sum defined by a difference between the pilot tones of a first group of N symbols and a corresponding pilot tones of a second group of N symbols preceding the first group of N symbols, computing a second sum defined by the pilot tones of the second group of N symbols, and computing a ratio of the first sum and the second sum for each of the N symbols of the first and second group of symbols to generate N ratios representative of the Doppler spread of the channel. The first sum is further defined by the square of the difference between the pilot tones of the first group of N symbols and the corresponding pilot tones of the second group of N symbols.
Claims15
A computer-implemented method of estimating a Doppler spread of a channel of a communication system, the method comprising:
- computing, using the computer, a first sum defined by a difference between a plurality of pilot tones of a first group of N symbols and a corresponding plurality of pilot tones of a second group of N symbols preceding the first group of N symbols, wherein N is an integer greater than one;
- computing, using the computer, a second sum defined by the plurality of pilot tones of the second group of N symbols;
- and
- computing, using the computer, a ratio of the first sum and the second sum for each of the N symbols of the first and second group of symbols thereby to generate N ratios representative of the Doppler spread of the channel.
A system configured to estimate a Doppler spread of a channel of a communication system, the system comprising:
- a first summing block configured to compute a first sum defined by a difference between a plurality of pilot tones of a first group of N symbols and a corresponding plurality of pilot tones of a second group of N symbols preceding the first group of N symbols, wherein N is an integer greater than one;
- a second summing block configured to compute a second sum defined by the plurality of pilot tones of the second group of N symbols;
- a memory configured to store the first and second sum;
- and
- a processing block configured to compute a ratio of the first sum and the second sum for each of the N symbols of the first and second group of symbols thereby to generate N ratios representative of the Doppler spread of the channel.
A system configured to estimate a Doppler spread of a channel of a communication system, the system comprising:
- a processing unit configured to:
- compute a first sum defined by a difference between a plurality of pilot tones of a first group of N symbols and a corresponding plurality of pilot tones of a second group of N symbols preceding the first group of N symbols, wherein N is an integer greater than one;
- compute a second sum defined by the plurality of pilot tones of the second group of N symbols;
- and
- compute a ratio of the first sum and the second sum for each of the N symbols of the first and second group of symbols thereby to generate N ratios representative of the Doppler spread of the channel;
- and
- a memory configured to store the first and second sums.
Dependencies are inferred from the claim text.