Apparatus and method for OFDM data communications

Abstract

A radio system employing Orthogonal Frequency Division Multiplexed (OFDM) includes a Base Transceiver Station (BTS) along with a number of mobile terminals located within a coverage area of the BTS. In this system, a target mobile terminal is provided with a focused transmission beam to receive high data rate traffic information while the remainder of the mobile terminals are provided with pilot and signalling information. To achieve both objectives, a BTS is implemented with a transmission apparatus that generates a directional transmission beam for the data traffic information. In one design, this directional beam transmits the pilot and signalling information along with the data traffic information by rotating the beam within the coverage area. In another design, the BTS has a transmission apparatus that generates more than one transmission beam. In one case, the BTS transmits a directional transmission beam for the data traffic information required by the target mobile terminal and a second broad transmission beam for the pilot and signalling information required by the all of the mobile terminals. In another case, the BTS transmits two directional transmissions beams, one beam for data traffic information and one rotating beam for pilot and signalling information.

1 . A Base Transceiver Station (BTS) arranged to communicate with a plurality of mobile terminals within a coverage area, the BTS comprising: 
 means for receiving service and data traffic information;    means for transmitting the service information on a first set of carriers to the mobile terminals within the coverage area; and    means for transmitting the data traffic information with high link gain on a second set of carriers to the target mobile terminal.    
   
   
       2 . A method of transmitting service and data traffic information to a plurality of mobile terminals within a coverage area, at least one of the mobile terminals being a target mobile terminal, the method comprising: 
 receiving service and data traffic information;    transmitting the service information on a first set of carriers to the mobile terminals within the coverage area using a first transmission beam; and    transmitting the data traffic information on a second set of carriers to the target mobile terminal using a second transmission beam.    
   
   
       3 . A method of transmitting service and data traffic information to a plurality of mobile terminals within a coverage area, at least one of the mobile terminals being a target mobile terminal, the method comprising: 
 receiving service and data traffic information;    transmitting the service information on a first set of carriers to the mobile terminals within the coverage area with a directional transmission beam;    transmitting the data traffic information on a second set of carriers to the target mobile terminal with the directional transmission beam; and    modifying the direction of focus of the directional transmission beam in order for each of the mobile terminals within the coverage area to receive the processed service information.    
   
   
       4 . A mobile terminal arranged to communicate with a Base Transceiver Station (BTS), the mobile terminal comprising: 
 a radio reception apparatus that operates to receive and process service information on a first set of carriers from at least one first transmission beam and to receive and process data traffic information on a second set of carriers from at least one second transmission beam; and    a monitor apparatus, coupled to the radio reception apparatus, that operates to determine if one or more of service information and data traffic information has been received at the radio reception apparatus; if only service information has been received, to instruct the BTS to attend to the received service information; if only data traffic information has been received, to instruct the BTS to attend to the received data traffic information; and if service and data traffic information has been received, to instruct the BTS to attend to both the received service and data traffic information.