| 摘要 |
PURPOSE:To simplify the decision control of a communication frequency between a portable terminal equipment and an on-vehicle repeater and to maintain a high service performance even to the portable terminal equipment whose transmission power is small by using a micro zone in a city and using a small zone in the suburb so as to apply efficient frequency allocation to each zone within the range of the assigned frequency band. CONSTITUTION:The frequency band for communication between a portable terminal equipment 23 and an on-vehicle repeater 24 in a small zone and a frequency band for communication between on-vehicle terminal equipments 15, 25 or between the on-vehicle repeater 24 and a base station are classified in the following. The frequency band assigned to the system is divided uniformly into (K+1) (K is a positive integer over 2) sub groups, and the one sub group is used for the communication between the on-vehicle repeater 24 and the portable terminal equipment 23 and the remaining K sets of sub groups are used for the communication between the base station 24 and the on-vehicle repeater 24. Thus, high service performance is maintained even to the portable terminal equipment 23 whose transmission power is small and the decision control of the communication frequency between the portable terminal equipment 23 and the on-vehicle repeater 24 is much simplified. |
