| 摘要 |
PURPOSE: To attain same wide area transmission by using a common spread code series by plural base stations and to freely revise a wide calling area by revising the base stations using the same spread code. CONSTITUTION: Narrow band signal modulators 11, 12 modulate respectively transmission data to a wide area and transmission data to a narrow area respectively by using, e.g. a BPSK (BinaryPhase-Shift-Keying). Then spread devices 13, 14 apply spread processing to a respectively signal to a wide area and a transmission signal to a narrow area by using spread codes for wide area and narrow area generated by a spread code series generator 15. Furthermore, an adder 17 adds signals and a transmission power amplifier 18 amplifies the signal and the amplified signal is sent from an antenna 19. Then a receiver being a mobile terminal equipment receives data for a wide area and data for a narrow area to be received by selecting the spread code series for inverse spread processing. The carrier frequency is the same for the wide area and the narrow area. |
