AMPS operation: A simple diagram of how AMPS system handles various calls and other responsibilities as shown in below diagram. As the power up, all mobile station is in the range of a base station which go through a registration with AMPS before actual service starts. According to the stateRead More →
Interpolation Process Implementation: Theory: “Upsampling” is defined as the process of inserting zero-valued samples between original samples to increase the sampling rate. (This is called “zero-stuffing”.) . “Interpolation”, is determined as the process of upsampling followed by filtering. The filtering removes the undesired spectral images. The main reason for interpolatingRead More →
Introduction to some existing wireless systems: For wireless system we consider many factors as its needs such as call duration, traffic in adjacent cell, call rate, atmosphere condition and the terrain. Various characteristics are important to get an idea about how wireless system will work in the real-world for theRead More →
Decimation process implementation: Theory: “Decimation” is that the process of reducing the rate. “Down sampling” may be a more specific term that refers to only the method of throwing away samples, without the low pass filtering operation. The most important reason to decimate is simply to reduce the sampling rateRead More →
Steps involved in performing FIR filter operation Step I: Let’s enter the pass band frequency (fp) and stop band frequency (fq). Step II: And then get the sampling frequency (fs), length of window (n). Step III: Next calculate cut off frequency. Step IV: Use the boxcar, hamming, Blackman Commands forRead More →
Cell traffic load is typically characterised has the two important distributed parameters. Average number of mobile stations requesting the service (average call arrival rate (λ). Average length of time the mobile stations requiring the service (average holding time T). The offered traffic load is defined as a= λT. ForRead More →
The cellular system depends on the radio signal received by a mobile station throughout the cell and on the contours of signal strength emanating from the base station of two adjacent cells j and i. As from the above discussion, the signal strength goes down as moves away from theRead More →
The DTMF stands for “Dual Tone Multi-Frequency”, and maybe a method of representing digits with tone frequencies, so as to transmit them over an analog communications network, for instance, a telephone line. In telephone networks, DTMF signals are wont to encode dial trains and other information. Dual-tone Multi-Frequency (DTMF) signalingRead More →
Where has IIR filters are digital filters with infinite impulse response. Unlike FIR filters, they have the feedback (a recursive a part of a filter) and are mentioned as recursive digital filters, therefore. For this reason, IIR filters have far better frequency responses than FIR filters of an equivalent order. Unlike FIR filters, their phase characteristicRead More →
Fundamental concept of cellular system: Let see example of cordless telephone used at home which employed wireless technology, which has less coverage and smaller amount of power. All the users use same frequency range without much inference among users. Same frequency interference avoidance is used in cellular system with muchRead More →