Sideband Noise Mitigation in a Co-Located Network Involving CDMA2000 and WCDMA System
Nosiri Onyebuchi Chikezie,
Onoh Gregory Nwachukwu,
Chukwudebe Gloria Azogini,
Azubogu Austin Chukwuemeka
Issue:
Volume 3, Issue 2, April 2014
Pages:
17-24
Received:
22 April 2014
Accepted:
12 May 2014
Published:
20 May 2014
Abstract: The installation of base station antennas within close frequency range in a co-located scenario constitutes a major interference for radio spectrum engineers. In a co-located setting involving a downlink frequency of CDMA2000 (1960 -1990MHz) and an uplink frequency of WCDMA (1920-1980MHz) as used in the telecommunication industry in Nigeria, the base station receiver is required to receive low amplitude desired signals in the presence of strong transmitting power signals resulting to sideband noise interference. The paper identifies the major mechanism of the sideband noise and proposes the application of a Butterworth Band Pass Filter (BBPF) as a mitigation technique. The technique was developed through the applications of empirical and mathematical analysis conducted in two different scenarios to evaluate the levels of the interference signals on the WCDMA receiver from CDMA2000 transmitter. The first scenario involved a standalone un-collocated WCDMA network while the second scenario involved a co-located network (CDMA2000 and WCDMA). A 52dB required attenuation specification was obtained for the BBPF design.
Abstract: The installation of base station antennas within close frequency range in a co-located scenario constitutes a major interference for radio spectrum engineers. In a co-located setting involving a downlink frequency of CDMA2000 (1960 -1990MHz) and an uplink frequency of WCDMA (1920-1980MHz) as used in the telecommunication industry in Nigeria, the ba...
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Analysis of the Automatic Transmission Fault Diagnosis Based on Bayesian Network Sensitivity
Luo Jin,
Ma Qihua,
Luo Yiping
Issue:
Volume 3, Issue 2, April 2014
Pages:
25-28
Received:
3 June 2014
Accepted:
17 June 2014
Published:
30 June 2014
Abstract: Automobile automatic transmission is a complex system integrates machine, electricity, liquid, in terms of its fault diagnosis has the characteristics of uncertainty and high complex correlation, thus put forward the Bayesian network based on the theory of probability and theory of the fault tree for fault diagnosis methods of automobile automatic transmission, it has a certain value for application. Take a failure automatic transmission as an example, analyzes the causes of the automatic transmission fault and the relationship between the affecting factors, according to the properties of the automatic transmission fault establishes a Bayesian network model, and through calculating sensitivity to determine the probability of a certain causes to the automatic transmission fault. The results show that the method is operable in automatic transmission fault diagnosis, diagnosis results are accurate and credible.
Abstract: Automobile automatic transmission is a complex system integrates machine, electricity, liquid, in terms of its fault diagnosis has the characteristics of uncertainty and high complex correlation, thus put forward the Bayesian network based on the theory of probability and theory of the fault tree for fault diagnosis methods of automobile automatic ...
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