Personal mobile communications in microwave band

The mobile communications technologies have been extremely-evolved during the past few years. The various types of mobile communications services such as mobile telephone, paging, teleterminal and so-on are in operation in many countries. The analogue cellular system is migrating to the digital cellular system and the high speed data services in the paging system will be launched in the near future. Under those circumstances, the radio spectrum will be lacked in most of countries and the allocation of new frequency band such as quasi-microwave, microwave, and/or millimeter wave will be necessary for the future mobile communications systems. This paper will discuss the technical solution in using the microwave band for the mobile communications area based upon the PHP (Personal Handy Phone) techniques in Japan. And also, the wideband transmission technique for the future multi-media mobile services in the microwave band will be discussed.