Switching System

We are offering switching system with the wll system, a switching system can controls a number of bts automatically by setting up data transmission lines with them. Wll system allows btss located certain distances from each other to reuse frequency by utilizing the frequency allocation technique in consideration of interference for the cell sites with low level of output.
Code division multiple access (cdma) based on digital cellular technology operates under the interference limit environment not the band limit of time division multiple access (tdma) and frequency division multiple access (fdma), and is superior to the other two mechanisms in terms of subscriber capacity. Tdma can accommodate three times more subscribers than fdma and cdma exceeds fdma by 12 to 15 times.
Cdma technology can be explained as follows: if two persons want to speak at the same time, they can take turns with one person speaking at the time or two rooms can be provided one to each. The first approach is tdma and the second one is space division multiple access (sdma). Or for example two persons sing at the same time, one in soprano and the other one in base tone, and the audience have a device filtering only the tone that they want to hear. This is cdma approach. With the technology, no matter how many singers sing a song or how many languages are spoken at the same time, the audience can filter what they want to without being confused as long as they are in different tones and in different languages.
In cdma, each signal has unique pseudo random binary sequence which is used to spread spectrum of carriers. Multiple of cdma signals share a frequency spectrum on which they are displayed being overlapped with each other. Coherent detector selectively receives the signal energy with matching pseudo random binary sequence and restores the spectrum. Signals with mismatching codes are considered inferences as the spectrum are not restored and are processed as noises.