Signal monitoring system for wireless network operation and management

In the last few years, various types of wireless networks have become available and cost-effective for commercial applications. In order to become a real alternative to traditional wireline telecommunications, wireless networks should provide competitive quality, reliability and availability of service. These requirements imply a need for a wireless fault management system with features similar to those incorporated in wireline counterparts. Despite a significant need for fault management in wireless networks, there has been almost no such proposals nor deployments. Existing wireless fault management systems provide management of mobile switching centers (MSG), rarely of base stations. Traditionally, base stations measure signal quality, and send alarms to a network management center (NMC) if some of the signal parameters are out of allowed range. This solution has been proven to be insufficient since it is possible to detect the signal quality at a base station's site, not at a subscriber's site. The proposed overlay signal monitoring system collects various signal parameters at a subscriber's site, determines if these parameters are within the allowed range of values, and generates an alarm if it is not the case. The NMC receives alarms and handles them as in wireline networks. This paper describes elements of the signal monitoring system, and how it detects and locates base station failures, signal degradation, co-channel and adjacent channel interference in a network. A mechanism for alarm generation and reporting is also described, as well as the interface between the signal monitoring system and existing network management center.