The Right Interconnection

While it has become more than clear that emergency response agencies need the ability to communicate with one another during a crisis, building a shared communications system is prohibitively costly. Gateways are an intermediate approach to interoperability because they require only minor modifications to existing radio infrastructure, thus costing much less than the development of shared systems. Gateways range in sophistication from simple devices that link two radio channels to advanced systems that can connect hundreds of devices operating on different public safety bands. The system is also capable of connecting trunked talk groups, encrypted networks, the public telephone network, cell phones, and satellite transmissions. Gateway devices are deployed as fixed-site, mobile, or portable units. Fixed-site units are usually used to provide continuous interoperability to a large geographical area that has overlapping or adjacent jurisdictions. On the other hand, mobile gateway devices are usually mounted in a vehicle that acts as the mobile command post. These mobile devices run on the power supply of the vehicle and typically transmit at 3 to 110 watts. Hand-held or portable units are lightweight, small units that are meant to be carried. The drawbacks are that they are less powerful and have fewer capabilities than the mobile unit. Mobile and portable devices are generally deployed to provide temporary interoperability at a crisis site. One major limitation of the gateway devices stems from the fact that radio spectrum is a limited resource that is tightly controlled. Hurricane Katrina is offered as an example of a crisis in which the devices were not managed correctly, resulting in further communications complications caused by too many agencies attempting to use the same channel. However, with appropriate management and nationwide standardizations, the gateway devices offer a valuable resource for emergency communications interoperability.