GL Conveys its Expertise in Simulcast Radio Systems

Gaithersburg, Maryland (PRWEB) August 07, 2012

GL Communications Inc. a leader in providing PC-based test, analysis and simulation products and consulting services to the worldwide telecommunications industry, conveyed today its expertise in Simulcast Radio Systems a unique communications technique used in public safety communications systems.

Speaking to the press, Mr. Vijay Kulkarni, CEO of the company said, Public safety personnel (police, fire, bus, rail, and emergency) rely on seamless wide area radio communications coverage to effectively perform their daily tasks. Typically a city/country will need to serve several hundred square miles or more with a handful of radio channels. A dispatcher may need to reach anyone in the serving area. But engineering wide area radio coverage with limited radio spectrum and limited number of radio channels is not easy. Generally many transmitter / receiver sites are required to get the widest possible coverage for mobiles and portables, for improved voice and data quality, and for better building penetration.

“Cellular systems use many small cells, small towers, and reuse frequencies in non-adjacent cells to achieve wide area coverage. This requires that individual radios be able to switch frequencies and the radio system be able to “handoff” from one base station to a neighboring base station as the radio user roams from one cell to the next.

He added, This level of complexity is not always affordable or readily available to the public safety band. To achieve wide area radio coverage, public safety agencies divide the problem into two – “talk out coverage” and “talk in coverage”. “Talk out coverage” is communications from a dispatcher to field personnel, or also called downlink coverage. Many solutions exist to achieve the widest possible “talk out” coverage, including: Employing multiple transmitter sites, Increasing transmitter power if FCC allows, Raising the transmitting antenna height, or tower height, if FAA allows and Directing the antenna patterns optimally and so on.

“”Talk in” coverage – is communications from field personnel to dispatchers, or also called uplink coverage. Possibilities for improving coverage here include: Multiple receiver sites with central “voting receivers”, Pre-amplifiers at the top of a tower to boost the signal from low power portables, Vehicular repeaters for portable talk-around coverage.

“”Talk-out” coverage can be greatly improved by simulcast transmission. Simulcast is the concatenation of two words “simultaneous” and “broadcast”. It is the simultaneous transmission of audio on the same frequency from two or more sites. Wide area coverage is possible with multiple transmitters. Normally if two or more transmitters were to transmit the same signal, a receiver in the field would “lock” or “capture” the stronger of the signals. If the signals are within

GL Conveys its Expertise in Simulcast Radio Systems