Patent ID: 8488691
Filing Date: 2013-07-16
Classification: H04L,H04W

Abstract:
1. A method for adaptive loading in an orthogonal frequency division multiplexing (OFDM) communication system, comprising: grouping sub-carriers into at least one of a plurality of classes, wherein the grouping is based upon feedback, and wherein each class has an associated data rate; de-multiplexing encoded data bits, sized less than an OFDM frame, to correspond to the at least one of a plurality of classes, wherein the encoded data bits are rate adapted in order to correspond to the class' associated data rate; buffering the rate adapted data bits according to the at least one of a plurality of classes, wherein each class has an associated buffer; performing inter-class boundary mitigation on the buffered rate adapted data bits by selecting one or more of the following: processing an entire class per symbol, using a highest quality class “Z” as a transition class, use a bottom class as a transition class, taking bits from another class when needed for additional transitions and collapsing the remainder into a lower class, increasing receiver (RX) CSI feedback, determining boundary classes, employing receiver (RX) feedback as to the best tones for a class prior to quantization for use at transitions, and performance back off to mitigate inter-class boundary effects; and mapping the buffered data onto the corresponding group of sub-carriers for data transmission.