User Context Aware Base Station Power Flow Model

At present the testing of power amplifiers within base station transmitters is limited to testing at component level as opposed to testing at the system level. While the detection of catastrophic failure is possible, that of performance degradation is not. This paper proposes a base station model with respect to transmitter output power with the aim of introducing system level monitoring of the power amplifier behaviour within the base station. Our model reflects the expected output levels of second or third generation CDMA base stations conforming to the Open Base Station Architecture Initiative (OBSAI) open base station reference architecture. The simulated base station output power is verified by comparison to field data using such metrics as power complementary cumulative distribution function (CCDF), volatility, absolute deviation, mean absolute deviation and rate of change

Base Station Performance Model

At present the testing of power amplifiers within base station transmitters is limited to testing at component level as opposed to testing at the system level. While the detection of catastrophic failure is possible, that of performance degradation is not. This paper proposes a base station model with respect to transmitter output power with the aim of introducing system level monitoring of the power amplifier behaviour within the base station. Our model reflects the expected output levels of second or third generation CDMA base stations conforming to the Open Base Station Architecture Initiative (OBSAI) open base station reference architecture. The simulated base station output power is verified by comparison to field data using such metrics as power complementary cumulative distribution function (CCDF), volatility, absolute deviation, mean absolute deviation and rate of change

A Fault Diagnosis Mechanism for a Proactive Maintenance Scheme for Wireless Systems

This paper presents the fault diagnosis mechanism for a proactive maintenance scheme for wireless systems which is aimed at reducing the high operational costs encountered in the wireless industry by decreasing maintenance costs and system downtime. An on-line monitoring system, based on the aforementioned fault diagnosis mechanism, is used to identify performance degradation, as well as its possible sources, so as to ensure that maintenance occurs only when necessary

A Fault Diagnosis Mechanism for a Proactive Maintenance Scheme for Wireless Systems

This paper presents the fault diagnosis mechanism for a proactive maintenance scheme for wireless systems which is aimed at reducing the high operational costs encountered in the wireless industry by decreasing maintenance costs and system downtime. An on-line monitoring system, based on the aforementioned fault diagnosis mechanism, is used to identify performance degradation, as well as its possible sources, so as to ensure that maintenance occurs only when necessary

Physical component performance degradation detection based on error probability analysis

The detection and diagnosis of physical layer faults at system level in communications systems remains problematic. This paper presents a cross layer fault detection scheme, suitable for implementation at higher levels in a communications system,with the ability to detect and diagnose the cause of physical layer failure which results in impaired performance. It is based on the distribution of symbol error frequency and the probability of error of the underlying modulation scheme used in the communications system. With this knowledge, a simple counting algorithm is proposed as a diagnostic tool to implement the methodology

Audit Firm Rotation Concerns And Considerations

The Public Company Accounting Oversight Board (PCAOB) issued a concept release in 2011 which proposes a mandatory audit firm rotation. However, PCAOB indicates that there is a limited amount of empirical data and research evidence on the potential costs and benefits of such mandatory audit firm rotation. This study provides some empirical evidences related to PCAOBs concerns. Specifically, we find that the largest clients audited by Big 4 accounting firms have few material internal control weaknesses and accounting restatements. In addition, accounting restatements are often reported within four years after the beginning of accounting errors and are reported by the same auditor during the restatement period. These findings cast doubt on the benefit of mandatory audit firm rotation. We also find that the largest audit clients on average represent over 20% of the audit revenues of local offices of Big 4 accounting firms. Thus, mandatory audit firm rotations could significantly disrupt the normal operations of public accounting firms if audit clients are required to change auditors periodically