Patent ID: 7376117
Filing Date: 2008-05-20
Classification: H03M,H04B,H04L

Abstract:
1. Interleaving circuit for a multiband OFDM (orthogonal frequency division multiplexing) transceiver of an ultra wide band wireless personal access network transmitting OFDM modulated symbols, wherein each OFDM symbol consists of a predetermined number (N CBPS ) of encoded bits, said interleaving circuit comprising: (a) a symbol interleaving unit which receives an input bitstream of encoded bits and permutes adjacent bits of said input bitstream across different OFDM symbols; (b) an intra-symbol tone interleaving unit which receives the bits permuted by said symbol interleaving unit and permutes adjacent bits of each OFDM symbol across uncorrelated data sub-carriers; (c) an intra-symbol cyclic shift unit which shifts cyclically N wherein each OFDM symbol is forwarded by said interleaving circuit to a frequency spreading unit which depending on data rate spreads the OFDM symbols in the frequency domain with an adjustable frequency spreading factor (FSF); wherein the frequency spreading unit is connected to an OFDM modulator which performs for each sub-carrier of the frequency band depending on the data rate either a DCM modulation or a QPSK modulation; wherein the OFDM modulator is connected to a time spreading unit which depending on an operation mode of said OFDM transceiver spreads the OFDM symbols in the time domain with a time spreading factor (TSF); wherein the time spreading unit is connected to a transmitter which transmits each interleaved OFDM symbol in different frequency bands according to a predetermined frequency hopping pattern comprising a corresponding pattern periodicity (P); wherein the least common multiple of the set of frequency hopping pattern periodicities (P