V.21 preamble tone detection method of base station controller in the WLL system

摘要

1. the art that the invention defined in the claims; The present invention will on the V.21 preamble tone detection method for a Wireless Local Loop (WLL) systems in the control station.; 2. The invention attempts to solve the technical challenges; The invention, WLL for providing the data service according to an analog fax call by the V.21 preamble incoming tone via the in-band service data when the vocoder within the V.21 preamble tone detecting unit of the control station is detected by software. intended to provide a V.21 preamble tone detection method in the controller system.; 3. Resolution of the subject matter of the invention,; The present invention according to the preamble tone detection method in a wireless network system, when a fixed subscriber to the landline subscriber matching device that is connected to the (Local Exchange) LE is trying to call to a mobile subscriber of Wireless Subscriber Line device, control by detecting the level of a signal in a preamble tone detector domestic vocoder, comprising: a first step of storing the actual incoming signal over a predetermined level in the buffer; A second step of the fast Fourier transform (FFT) for the incoming signals stored in said buffer, determine the characteristics of the signal with frequency component; The fast Fourier transform (FFT) by measuring the energy per frequency band, compare the signal energy of the signal energy in the high frequency range of from low frequency region by, if the incoming signal is a voice signal or a tone or V.21 preamble a third step of determining; And according to the determination result of the third step, wherein the incoming signal by performing a request to change service options selected when V.21 preamble tons processor and switch to the mode data service, the data service according to an analog fax incoming call Do a fourth step of providing.; 4. An important use of the invention,; The invention yiyongdoem WLL system or the like.