Digital modulation wireless devices are well suited for effective data transmission at specific radio frequencies, which are now limited resources, available bands of frequencies being narrower than conventional FM radio equipments. Combined with the improving transmission efficiency, the user-friendliness of these devices is thus greatly increasing. On the other hand, FM radio equipments are able to pick up communications to some extent if the noise of the environment is at the level of reception sensitivity or below, while digital radio equipments are either able to pick up the communication or not. Depending on conditions, trouble may occur in which communication is interrupted and cannot be understood . This tendency becomes pronounced in mountain areas and spaces between buildings in urban areas, and the use of digital radios in such 'dead zones' is a problem.
JRC integrated its strong expertise in GPS technology and radio equipment technology, and has commercialized an advance base station which is excellent in dealing with dead zones.