| 摘要 |
<p>A method for improving noise performance in a Radio Frequency (RF) transmitter that makes use of Orthogonal Frequency Division Multiplexing (OFDM). The method ° comprising the steps of: receiving a stream of digital data symbols in the form of symbol vectors, for RF transmission after multiplexing onto a subset of a set of sub- carriers according to OFDM and transforming each received symbol vector to the time domain; generating a first time domain cancellation vector from a basis vector that has the same dimensionality as the symbol vectors. In the frequency domain the basis vector has substantially zero value in each of the first subset of sub-carriers of the symbol vector and in the time domain the difference between a first element of the basis vector having the highest value and a second element of the basis vector having the next highest value is maximised. The method also comprises processing each symbol vector by subtracting the first cancellation vector from it to produce a modified symbol vector having reduced Peak-to- Average Power Ratio (PAPR) and then iteratively generating a new cancellation vector using the modified symbol vector, and producing a new symbol vector have reduced Peak-to-Average Power Ratio (PAPR). Other aspects include software for performing the method, an RF transmitter for transmitting OFDM with improved noise performance characteristics, and an OFDM signal with improved noise performance characteristics.</p> |
