Seung Hee Hong

US Patent:

20120183107, Jul 19, 2012

Filed:

Jan 16, 2012

Appl. No.:

13/351071

Inventors:

Mingrui Zhu - Irvine CA, US
Arun Kedambadi - San Diego CA, US
Seung Chul Hong - San Diego CA, US
Anand Anandakumar - San Diego CA, US

International Classification:

H04B 15/00

US Classification:

375348

Abstract:

A method and system for combining a guard interval and a corresponding portion of a received symbol, whereby when receiving a signal that contains the symbol with a guard interval corresponding to the symbol, a portion of the guard interval that is free from inter-symbol interference may be extracted, and the extracted portion of the guard interval may be combined with the corresponding portion of the symbol. The extracting and combining may be done after a determining, based on a delay profile provided by the received signal, that a delay spread is smaller than a predetermined channel delay. The delay spread may be determined by filtering an instantaneous delay spread associated with the received signal. The filtering may be performed using a 1-tap infinite impulse response low-pass filter. The low-pass filter may include a time constant that is the inverse of a maximum Doppler frequency shift.

US Patent:

20150222466, Aug 6, 2015

Filed:

Apr 15, 2015

Appl. No.:

14/687234

Inventors:

- Carlsbad CA, US
Arun Kedambadi - San Diego CA, US
Seung Chul Hong - San Diego CA, US
Anand Anandakumar - San Diego CA, US

International Classification:

H04L 27/26

Abstract:

Methods and systems are provided for adaptive guard interval (GI) combining. When a signal carrying at least one symbol that is preceded by a guard interval that comprises a portion of the symbol is received, a portion of the guard interval that is free from inter-symbol interference (ISI) may be determined, and only a part of the ISI-free portion of the guard interval may be extracted. The part of the ISI-free portion of the guard interval may be selected based on timing adjustment, relative to start of the symbol, that is applied to a function used in extracting the symbol. The extracted part of the ISI-free portion of the guard interval may then be combined with a corresponding portion of the symbol. The extracting and/or combining may be performed after a determination that a delay spread is smaller than a predetermined channel delay.