Methods and systems for diversity combining of synchronization statistics in OFDM systems
AssigneeOlympus Corporation
InventorsDumitru Mihai Ionescu, Abu Amanullah, Ghobad Heidari-Bateni
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Abstract
Various embodiments of the systems and methods described herein may be used to compute a minimum variance unbiased estimator by receiving a first OFDM signal at a pilot tone, receiving a second OFDM signal sent in the same frequency band and determining a differential phase metric between the first OFDM signal and the second OFDM signal. In some embodiments, the differential phase metric may be used to diversity combine synchronization statistics. In various embodiments, the differential phase metric may be used to detect a narrow-band interference.
Claims18
A method in an OFDM communications system implementing frequency hopping, comprising:
- receiving a first pair of OFDM symbols on a first frequency band;
- receiving a second pair of OFDM symbols on a second frequency band;
- obtaining a first pair of frequency domain representations of the first pair of OFDM symbols at a pair of pilot tones;
- obtaining a second pair of frequency domain representations of the second pair of OFDM symbols at the pair of pilot tones;
- forming a first frequency domain statistic for the first frequency band by multiplying one of the first pair of frequency domain representations with the complex conjugate of the other of the first pair of frequency domain representations;
- forming a second frequency domain statistic for the second frequency band by multiplying on of the second pair of frequency domain representations with the complex conjugate of the other of the second pair of frequency domain representations;
- and
- combining the first frequency domain statistic with the second frequency domain statistic to form a combined frequency domain statistic.
A system for use in an OFDM communications system implementing frequency hopping, comprising:
- a transceiver;
- a processor, coupled to the transceiver;
- and
- a memory, coupled to the processor and configured to store instructions causing the processor to perform the steps of:
- receiving a first pair of OFDM symbols on a first frequency band;
- receiving a second pair of OFDM symbols on a second frequency band;
- obtaining a first pair of frequency domain representations of the first pair of OFDM symbols at a pair of pilot tones;
- obtaining a second pair of frequency domain representations of the second pair of OFDM symbols at the pair of pilot tones;
- forming a first frequency domain statistic for the first frequency band by multiplying one of the first pair of frequency domain representations with the complex conjugate of the other of the first pair of frequency domain representations;
- forming a second frequency domain statistic for the second frequency band by multiplying on of the second pair of frequency domain representations with the complex conjugate of the other of the second pair of frequency domain representations;
- and
- combining the first frequency domain statistic with the second frequency domain statistic to form a combined frequency domain statistic.
Dependencies are inferred from the claim text.