Radio-over-IP (RoIP) explained

What is Radio over IP?

Radio over Internet Protocol (RoIP) is a methodology of transmitting and receiving radio communications via Internet Protocol (IP), a data communications standard used to power the Internet as well as home, business and government computer networks.

If you understand the concept of Voice over IP (VoIP), Radio-over-IP is basically the same thing with an added command layer to control basic radio functions such as push-to-talk (PTT), frequency change, etc.

VoIP was originally used to enable voice communications over data networks using the TCP/IP protocol, i.e. LAN, WAN and the Internet. VoIP has virtually put some telco’s out of business, negating the need for separate lines for telephone (voice) and Internet (data). Now a single data connection can provide voice, data, video and other services. Cable TV vendors have capitalized on this technology, becoming your Internet Service Provider (ISP) as well as your phone company, offering the convenience and cost savings of a single provider of all three services.

Land mobile radio (LMR) vendors soon recognized this opportunity and began utilizing VoIP channels to carry radio radio traffic to remote sites, effectively hitching a free ride on existing data links without the expense of additional copper leased-lines or radio/microwave links.

Computer-aided dispatch (CAD) systems historically used EIA tone remote control to operate radios installed at a different locations. The connection was normally made with twisted-pair telephone lines, 2 or 4 wires per radio. As is usually the case with analog systems, the distance may be limited by cable length, quality and signal loss. This method is still very widely used today, but new systems typically use RoIP, thus a single Ethernet cable can carry multiple radio links as well as other voice & data services.

What can RoIP do for me?

In its most basic form, RoIP technology provides an method of linking two or more radios or repeaters using a LAN/WAN or Internet connection. This is known as Site Linking or Point-to-Point linking.

Another common application is IP Dispatch or remote base station. Like tone remote, this allows users the ability to operate transceivers remotely, but distance is not limited by cable length. Dispatchers use a software-based IP Console which typically runs on the Windows™ operating system, or in some cases Linux.

Radio-over-IP has become a major enabler of interoperability, allowing otherwise incompatible radio systems to communicate seamlessly, sharing a common data connection.

Push-to-talk for for mobile phones and PDAs, known as P2T may be used in conjunction with RoIP networks. This allows SmartPhone users to communicate directly with radio users and dispatchers. Now a cell phone can double as a two-way radio.

Site Linking

The first and most basic use of RoIP is using the Internet or LAN/WAN to link two radio sites together. Providing both sites already have Internet, this is a very cost-effective solution. Traditionally, linking sites required a leased telephone line or installation of an RF link with radios, antennas, hard-line, and additional tower space. If the locations are not line-of-sight from eachother, it might require 2 or more hops to make the link. RoIP has no distance limitation, so long as both sides are on the same network or Internet.

IP Dispatch

Using a “soft console” or other RoIP software, users can operate radios remotely – from anywhere that has Internet or network connection. Soft console apps are available for a wide variety of devices including desktop computers, laptops, tablets and PDAs. Deployments range from a single user controlling a single radio, to full E-911 dispatch centers with multiple operators controlling dozens of radios at several locations.

Interoperability

One of the most exciting applications of RoIP technology is its ability to quickly and easily bridge the gap between otherwise incompatible radio systems. Each radio is connected to a universal radio interface via the microphone jack or auxiliary connector. At a minimum, all that’s needed is RX audio, TX audio and PTT control. Some more advanced systems offer additional radio controls, such as frequency change, monitor, ANI, etc.

P2T

New P2T apps for smart-phones can eliminate the need to carry a radio as well as a cell phone. An added advantage is the virtually unlimited range offered by cell phones. An LMR radio can access only the local or regional radio network it is programmed and authorized for. A cell phone however, is able to utilize national and even international networks covering more than 95% of the population. For example, a P2T user can carry on a 2-way conversation with radio users from the next county or from across the country.

To find out how ComTekk’s Radio-over-IP applications can work for you, please Contact Us.