Patent ID: 8559459

Claim:
A bandwidth allocating control apparatus for use in an optical communication base station forming an optical access system together with a plurality of optical communication subscriber terminal units and connected communicable with the subscriber terminal units, wherein said apparatus has a reception bandwidth from the subscriber terminal units divided into a bandwidth for short distance and a bandwidth for long distance, and said apparatus is responsive to a data transmission request received from any one of the subscriber terminal units to allocate the reception bandwidth on a basis of a communication distance from the base station to the one subscriber terminal unit so that, when the one subscriber terminal unit is classified into a short-distance subscriber terminal class, the bandwidth for short distance is allocated to the one subscriber terminal unit corresponding to a volume of data the one subscriber terminal unit requests to transmit, and, when the one subscriber terminal unit is classified into a long-distance subscriber terminal class, a predetermined bandwidth in the bandwidth for long distance is allocated to the one subscriber terminal unit, said apparatus comprising: a residual bandwidth calculator for calculating a residual bandwidth of the bandwidth for short distance remaining unallocated after having allocated the reception bandwidth to the one subscriber terminal unit, when classified into the short-distance subscriber terminal class; a middle-distance subscriber terminal classifier for using a middle-distance boundary calculation model defining a relationship between the residual bandwidth and the communication distance to further classify the one subscriber terminal unit, when classified into the long-distance subscriber terminal class, into a middle-distance subscriber terminal class or the long-distance subscriber terminal class; and a middle-distance bandwidth allocator for further allocating the residual bandwidth to the one subscriber terminal unit, when classified into the middle-distance subscriber terminal class in addition to the predetermined bandwidth allocated, said apparatus transmitting allocation information on allocating the residual bandwidth to the one subscriber terminal unit, when classified into the middle-distance subscriber terminal class.