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Basis for optimum signal coverage crucial

Whether a municipality is deploying WiFi or mobile WiMAX, it’s crucial to carefully define the basis for optimum signal coverage. In many instances, I’ve seen this get very little attention in RFPs and contracts, and as a result, the system generally ends up not providing adequate levels of performance. You certainly want to avoid only stating that “the system shall offer optimum signal coverage.” This doesn’t mean much unless you clearly define what constitutes optimum signal coverage.

For example, the definition of client radio types in a contract is often not clear. The problem is that radios from different manufacturers have varying transmit power, which affects the signal going from the client device to the mesh node (uplink path). (Generally, mesh nodes operate at higher transmit power, which precludes the downlink from offering any trouble.) Radios purchased from common retail stores, for instance, may have relatively low transmit power, resulting in limited range. This often leads to needs for a higher mesh node density to support required signal coverage areas, something that integrators and municipalities need to know at the beginning of the deployment. You definitely don’t want to wait and learn this after the network goes operational.

If lower-powered radios will need signal coverage support, avoid problems by having the RFP and contract specify the need to support radios having lower transmit power, such as those available from retail outlets. Don’t leave this as an assumption for integrators. On the other hand, if applications such as public safety dictate that vehicles should be equipped with client radios having relatively high transmit power, then stating this in the contract or RFP will likely result in a lower mesh node density. If the specific client radio type is known, then be sure to note the exact model to further aid the integrator in designing a system with optimum signal coverage.

This is just a single example of many items that you should clearly specify to enable optimum signal coverage. A few others involve specifics on performance, indoor coverage areas, mobility of end users, and physical changes, such as construction of new buildings. Just be sure to clearly define all applicable requirements to ensure successful implementation of a municipal wireless network.