Patent ID: 8537759

Claim:
A transmitting unit within a communications system where at least some part of the transmission is executed by radio waves and in cells, and where symbols are transmitted by Orthogonal Frequency Divisional Multiplexing, called OFDM-technology, between a transmitting unit and a receiving unit, at which the symbol transmission is executed over a transmission channel in blocks of binary digits and with a guard interval (GI) between the blocks, the transmitting unit comprising: circuitry configured to: determine a characteristic of a transmission channel between the transmitting unit and the receiving unit; determine a size of a cell in which the transmitting unit is located based on the determined characteristic of the channel; determine a smallest possible guard interval length that causes intersymbol interference below a predetermined threshold value based on the determined size of the cell; and automatically adjust a length of the guard interval to be the smallest possible guard interval length.