Patent ID: 8014264

Claim:
A method of generating a signal for wireless transmission in a communication system serving a plurality of cells, the method comprising: forming a plurality of signal transmission frames, wherein each transmission frame is partitioned into a plurality of subframes, and wherein each subframe is further divided into a plurality of time-slots; configuring each subframe with a predetermined ratio of downlink time-slots and uplink time-slots, wherein the predetermined ratio of a number of downlink time-slots and a number of uplink time-slots varies between two or more subframes; inserting at least one special downlink period (SDP) in a transmission frame, during which a base station broadcasts control information including a cell identity; inserting at least one special uplink period (SUP) in a transmission frame, during which a mobile station is capable of carrying out radio functions; and forming a plurality of orthogonal frequency division multiplexing (OFDM) symbols in one or more time-slots by: randomizing frequency-domain data before modulation; modulating the randomized data to produce modulated data symbols; inserting training symbols with the modulated data symbols; mapping the modulated data symbols and training symbols to frequency-domain subcarriers, wherein the subcarriers are grouped into subchannels to support scalability and multiple access; and converting the frequency-domain subcarriers to time-domain signals through an inverse Fast Fourier Transform (FFT), wherein at least two configurations for frequency-domain randomization are utilized to facilitate data transmission for two or more application services, the configurations for frequency-domain randomization including: a first frequency-domain randomization configuration that is different among individual cells, wherein the first frequency-domain randomization configuration is controlled by a cell identity of each cell and is used to facilitate data unicasting; and a second frequency-domain randomization configuration that is the same for multiple cells, wherein the second frequency-domain randomization configuration is used to facilitate data broadcasting.