No abstract

-A variable gain amplifier operating at 2.5 GHz based on Single Ended topology has been designed and characterized. Three such stages were cascaded preceded by a single stage LNA. A source follower is used at the output as an active load matching. Overall dynamic gain variation is 45 dB with a maximum gain of 47 dB. The -3 dB bandwidth is 0.800 GHz. A minimum noise figure of 0.81 dB is obtained in the highest gain mode. Maximum value of 1 dB compression at the output is -7.2 dBm and the corresponding third order intercept point is +5.3 dBm. Consumed DC power 285 mW and is immune to gain variation. The circuit is implemented with GaAs pHEMT technology. The combined area occupied by the multistage low noise VGA and the single ended VGA is 3.5 mm X 3 mm.

-A variable gain amplifier operating at 2.5 GHz based on Single Ended topology has been designed and characterized. Three such stages were cascaded preceded by a single stage LNA. A source follower is used at the output as an active load matching. Overall dynamic gain variation is 45 dB with a maximum gain of 47 dB. The -3 dB bandwidth is 0.800 GHz. A minimum noise figure of 0.81 dB is obtained in the highest gain mode. Maximum value of 1 dB compression at the output is -7.2 dBm and the corresponding third order intercept point is +5.3 dBm. Consumed DC power 285 mW and is immune to gain variation. The circuit is implemented with GaAs pHEMT technology. The combined area occupied by the multistage low noise VGA and the single ended VGA is 3.5 mm X 3 mm.

No abstract

In cellular mobile communication system the existing dynamic channel allocation scheme suffer from high blocking probability and forced termination probability. To mitigate this problem, in this paper we evaluated the performance of dynamic channel allocation scheme based on carrier-to-noise interference ratio. In our system model, uplink power strength from a call-initiating user to the base station is examined. This power is provided by the carrier-to-noise ratio (C/N). The channel search is conducted in the repeated channel numbers of that cell based on the carrier-to-noise ratio so that this system provides the low blocking probability and initiates large number of calls in dynamic channel allocation environment.We have presented the momentous performance in blocking probability and forced termination probability through this research.