Multi-band radios -- a concert of technology

   First, some background. Since the 1990s, public safety and federal radio communications spectrum requirements have increased dramatically as the need for more communication talk paths, more data channels, and more connectivity is required by a growing universe of government agencies and first responders.

   To keep up with this voracious appetite for additional channels, talk groups, and network capacity, the Federal Communication Commission (FCC) and the National Telecommunications and Information Agency have allocated spectrum in a variety of different frequency bands from 30 to 870 MHz. The first band was 30 to 50 MHz, which is still in use today by many agencies. Then, a progressive series of bands at higher frequencies was released from 136 to 174 MHz, 402 to 420 MHz, 450 to 470 MHz, 470 to 520 MHz, 800 MHz, and most recently, 380 to 400 MHz and 700 MHz bands. Each band has been accessed using a separate, specific, single-band radio. The traditional RF components and radio design approaches limited an economically viable design to a single band for each portable radio.

   Existing solutions just did not work. Although patching and switching equipment was available, and there was a common over-the-air standard under the APCO Project 25 (P25) effort, there were still no single transceivers available that could operate in all of the bands. It remained common for incident commanders and personnel to be carrying two, three, or even four radios in order to communicate with each other.

In your hand

   What will the right solution look like? Technology advancements and software-defined radio (SDR) techniques developed for the military now make it possible to have a single, portable multi-band radio (MBR) that operates on all of the primary public safety frequency bands, as well as bands used by the Department of Defense (DoD), federal agencies, and Marine frequencies used on the waterways. This new type of portable radio will also allow multi-mode operation on older legacy analog FM systems, newer P25 digital systems (both trunked and conventional), and will operate in both clear and encrypted modes using P25-specified 256 bit key Advanced Encryption Standard (AES) encryption.

   Using a new MBR, Channel 1 can be defined for a regional P25 trunking system, Channel 2 for a VHF analog channel used by a local volunteer fire department, Channel 3 for a UHF EMS frequency, Channel 4 for a P25 digital Federal Government frequency, and Channel 5 for a 700 MHz trunked system in a bordering municipality. Effectively, MBR brings interoperability in the palm of an officer's hand and a new tool to coordinate multi-agency response across multiple land mobile radio (LMR) systems.

   With 2.2 million first responders in the United States today, it is the expectation that each one will be able to connect with other personnel on scene, as well as with dispatch centers, with clear, reliable voice and data communications. Lives are at stake, and the radio is an essential tool to accomplish the mission. In many cases, the agency's needs go beyond this traditional use, and radio communications are used to coordinate the response of law enforcement, EMS, fire, transportation and federal agencies as they team to manage, direct and give aid at terrorist incidents, large sporting events, or natural disasters. The MBR can be a useful tool in the coordination of multiple agency resources for large regional events.

   Many law enforcement agencies are involved in special task force operations. These groups successfully combine the resources and unique expertise of a variety of agencies and personnel to address specific criminal elements and threats. The MBR creates a tool that allows these groups to operate and share channels on their home systems, as well as new systems to which they may travel for support.


   There are other capabilities an MBR solution should bring. First, being able to take advantage of existing infrastructure and also operate without infrastructure is key. The right solution would bridge between established regional P25 trunked systems and conventional radio users from adjacent municipalities using other bands.

   Flexible deployment is also essential, e.g., the ability to serve a single incident commander, a group of commanders, all squad leaders, or every team member as required. Improvements could be delivered across the broad cross section of users, from the smallest rural agencies to the largest urban systems.

   Ease of use is a priority as well. The radio must be easy to operate and quick to deploy. The familiarity that users would have with MBR technologies used in day-to-day operations would, in crisis situations, be life-saving.

   With maximum spectrum utilization, local users who have moved to 800 MHz systems but have kept older VHF and UHF conventional frequencies for back up, would be able to access all of these bands for additional talk paths. Federal users who have been frustrated by VHF spectrum crowding are now free to use the 402 to 420 MHz band along with their traditional VHF channels in a single portable radio.

   Many government agencies have created caches of portable radios maintained, pre-programmed, and at the ready to use for incidents and natural disasters. The MBR is perfect for this application as it gives users the ability to reach out to other responding agencies regardless of band. In addition, if radio system infrastructure is destroyed or off the air, the user has the ability to connect in alternative frequency bands that are still operational.

   A well-defined set of mutual aid channels, now with standardized channel names, exists nationwide for public safety and federal agency communications. This new radio will be able to host these channels in all of the major frequency bands to create immediate multi-agency communications links at an incident scene.

Preparation & implementation

   Technology is only part of the solution. Well-developed plans for incidents, natural disasters, and multi-agency cooperation at large public events are essential. Training for personnel at all levels is required to prepare in advance. Memoranda of Understanding for shared channels between agencies and operations are now in place in many regions of the country to support these plans.

   In addition, radio manufacturers must be committed to formal testing and to ensuring that the most reliable communications equipment is provided to law enforcement. Performance, emissions, intrinsic safety, P25 Compliance Assessment Program (CAP), and encryption are the baseline certifications and approvals that users should look for. The P25 CAP tests, for example, provide a means of verifying that radio equipment meets the P25 standard and will be interoperable in P25 systems. Federal grant dollars are being invested in standardized solutions that promote interoperability for the more than 60,000 emergency response agencies nationwide.

   One such solution now in the hands of first responders is Thales Communications' Liberty multi-band, multi-mode, software-defined radio. Thales has leveraged more than 10 years of P25 Public Safety experience and an unequaled SDR technology base serving DoD to develop the Liberty radio. In early 2008, the U.S. Department of Homeland Security (DHS) Science and Technology Directorate had awarded a contract to Thales to demonstrate a single MBR that enables emergency responders to communicate with partner agencies, regardless of the radio band on which they operate. That radio, the Liberty radio, became the first multi-band radio covering the entire Public Safety spectrum to be approved by the FCC. It operates across all the Public Safety bands (136 to 174 MHz, 380 to 520 MHz, 700 MHz, and 800 MHz) and in all modes (P25 conventional, P25 trunked, and legacy analog). It offers Output Feedback Data Encryption Standard and AES with over-the-air-rekey for secure communications. Mil-Spec rugged, the Liberty radio is submersible to 2 meters.

   Having undergone operational evaluation during 2009 — including use at the Presidential Inauguration, Kentucky Derby, multiple live burns, and other events — the Liberty radio is now in a pilot test under the DHS MBR Program. Each of the participating agencies will conduct a minimum 30-day pilot. The pilots are designed to focus on the capabilities and effectiveness of the technology, with users primarily in a command-and-control role or involved in special operations with multiple entities. Factors such as operating bands, partner agencies and disciplines, interoperable conditions, and geographic landscapes were considered when selecting pilot sites. Feedback provided by participants of this pilot program will help ensure that true interoperability is delivered to our nation's first responders.

   Stephen Nichols, first vice president of the Project 25 Technology Interest Group, has been with Thales Communications Inc. since 1997 leading business development activities for the company's Project 25 radio product lines.