Patent ID: 7512174
Filing Date: 2009-03-31
Classification: H04L

Abstract:
1. A communication system including a first communication apparatus and a second communication apparatus adapted to communicate with each other, wherein said first communication apparatus comprises: data rate selecting means for selecting one data rate from among a plurality of data rates; and communication signal transmitting means for transmitting a communication signal at the selected one data rate to the second communication apparatus, said second communication apparatus comprises: necessary received power data storing means for storing therein necessary received power data in correspondence to each of the plurality of data rates, the necessary received power data being received power data representing a received power; receiving means for receiving the communication signal transmitted by said communication signal transmitting means; received power data acquiring means for acquiring received power data representing a received power of the communication signal received by said receiving means; transmission power remaining data acquiring means for acquiring transmission power remaining data representing a difference between a maximum transmittable power of said communication signal transmitting means and a transmission power when said communication signal transmitting means transmits the communication signal; data rate determining means for determining a data rate to be selected by said data rate selecting means based on a maximum received power data estimated based on the acquired transmission power remaining data and the acquired received power data, and the necessary received power data; and data rate information transmitting means for transmitting data rate information representing the data rate determined by said data rate determining means to said first communication apparatus, said first communication apparatus further comprises data rate information receiving means for receiving the data rate information transmitted thereto, wherein said data rate selecting means selects the data rate in correspondence to the data rate represented by the data rate information, wherein said data rate determining means comprises: data rate acquiring means for acquiring a data rate of the communication signal received by said receiving means; and current rate received power data acquiring means for acquiring current rate received power data from the necessary received power data stored by said necessary received power data storing means in correspondence to the acquired data rate, the current rate received power data being the necessary received power data stored by said necessary received power data storing means, and said data rate determining means determines a data rate to be selected by said data rate selecting means based on the maximum received power data and the current rate received power data as the necessary received power data.