The primary goals of wireless network providers are often conflicting with the goals of the network manager. Wireless providers are rapidly acquiring new customers and expect the network managers to maintain the highest level of customer satisfaction for existing subscribers. Maintaining high levels of customer satisfaction minimizes turn around, which occurs when customers are dissatisfied with their current provider and switch to a competitor. As network managers we use utilization levels to indicate use. These utilization levels are required to predict how much bandwidth we need to offer to our customers in order for them to receive optimum performance. As a Network Manager we need to know what applications our customers use, how many customers we have or will have and the types of protocols they use in order to give them connectivity. Sometimes these protocols are given as standards and other times they are up for interpretation. Numerous customer service surveys have been conducted that indicate quality and performance are very important (Stenger). These surveys show how our customers perceive reliable quality and performance. We obtain reliable quality and performance through network optimization due to customer demands. What is optimum network performance? This means we use some form of performance metrics to evaluate the quality of our network, set the standard of our network and then continually raise the standard to become optimum for the requirements set forth, by customer demands. We will take a look at the network optimization process and discuss the process below.
In order to have peak optimum performance for wireless networks it is imperative to first do a site evaluation. It is necessary to perform a site eval to determine appropriate locations for our base station, repeaters and antennas. Ideal locations are surveyed and an analysis is performed between the two sites. This usually consists of transmitting a known calibrated continuous wave or CW signal from one location to the next and measuring it with a calibrated receiver (Carr). Careful calculations must be made due to the distances that could be involved. In the old days they used to do this site eval with mirrors and the suns reflectivity. Today we use GPS, handheld radios and sometimes weather balloons. Once the sites are located we move into the path analysis phase. The initial calculations that were performed are analyzed. In today’s Hi-Tech world this path analysis can be performed with the aid of expensive software, whereas not so long ago these calculations and analysis could be very time consuming and tedious. A path analysis takes into account the atmospheric conditions (weather), frequencies, the temperature, distance, latitude and longitude. In short, this is any characteristic that could cause a signal not to pass or to pass through the required medium of air. Radio waves through air at certain frequencies are very susceptible to conditions that cause the RF signal to bend, duct, fade, scatter or dissipate. Any one of these can cause a loss in performance, degradation of service, or loss of signal from or to the point of origin. These calculations are necessary to determine the optimum equipment for optimum performance. There are entire books written on the complexities of path analysis and is beyond the scope of this forum. A path analysis is performed on every network element. If this is an existing site then initial turn up data should be available to serve as a base metric. After we do a path analysis we find ourselves in the next stage called acceptance testing. This stage is one of the most critical for network optimization.