In addition to the commercial Radio Frequency (RF) trend that is rapidly accelerating the role of radio in the consumers everyday life, the military continues to be engaged in RF electronic warfare and communications. The 1% of the electronics market occupied by the Department of Defense (DoD) has demanded a niche market for RF qualified devices for some time.

The DoD, with its emphasis on commercial-off-the-shelf (COTS) and “open” systems, is beginning to become more interested in the more commercially-oriented RF devices as a means to leverage the volumes and innovations of the commercial world for military uses. Reliability, a subject of prime importance to the EMPF, is foremost in the use of these commercial breakthrough RF technologies, since the commercial materials are often not as rugged as the military ones.

The EMPF is helping the military face aging and potential obsolescence of three specific critical combat systems. The first is the AN/TRN-30 Beacon, whose EMPF sustainment/upgrade activities are documented in this issue of EMPFasis. The second is the ARS-6 CSAR (Combat Search and Rescue) system, the third is the AESA radar for the F/A-18 aircraft.

The new RF innovations are the ones that are now routinely used in cell phones, wireless enabled laptops, RFID tags for everything from retail to livestock, and automotive radars, to name just a few. To the extent that these commercial RF gadgets can be made to defer the obsolescence and/or enhance the features of the military system, they are of potential military value.

In the case of the ARS-6, a main innovation will be the addition in the EMPF redesign of the existing CSAR transponder of a Software Defined Radio. This type of radio has the trait that the “software definition” can be used to reprogram the radio to accept any of multiple different RF signals, RF frequencies, and RF signaling schemes (waveforms). In the commercial world, this type of “software defined radio” might be used to allow the construction of a cell site (base station) for cell phones that would accept any of the different cellular protocols (waveforms) that might be used by the cellular subscriber’s system, such as CDMA, TDMA, UMTS, PCS, CDMA 2000, or GSM. The requirement that the cell site accept any and all of these waveforms and frequencies will give the cellular network operator a revenue stream for each type of RF system instead of having to have cell sites built that specialize in only one at a time.

The concept outlined above is that of “software defined radio” and is being commercially applied not just to cellular networks, but to Homeland Security first responder networked radios to allow good communications and coordination of efforts between police, fire, ambulance, coast guard, FEMA, Port Authority, EMS, and trauma centers, regardless of what waveform or frequency they use. The lack of this capability on September 11, 2001 was a driving factor for this effort.

The military analogy is NATO (North Atlantic Treaty Organization) or a multi-nation coalition fighting a battle with each faction having a different radio frequency/protocol in use for its communication. The JTRS (Joint Tactical Radio System) is being developed in the military to address this problem. JTRS would use this Software Defined Radio system to allow communications/coordination between the various coalition assets. JTRS compatibility has become a buzz word for a desired future military feature for any RF System development.

The second of these EMPF upgrades of aging RF systems is the ARS-6 CSARS (Combat Search and Rescue) radio. The ARS-6 is the airborne radio used to locate a downed pilot or other survivor carrying one of several available types of handheld survival radios. The Software Defined Radio (1) which the EMPF will add to the existing ARS-6 in the EMPF re-design will allow multiple survivor locator assets to be coordinated. Optimal combination of GPS (Global Positioning System), SARSAT (Search and Rescue Satellite) and others that will add features to enhance the current CSARS system will be added in the EMPF redesign of this aging RF system.

Third but not least is the now-venerable (20+ years old) F/A-18. F/A-18 fist flew in 1979 and was fist operational in 1983. Inside the AESA (Active Electronically Steered Array) radar will be RF chips called MMICs (Monolithic Microwave Integrated Circuits) that will be attached to the radar by using flip chip assembly methodology. The flip chip attachment method, rather than conventional wire bonding, results in optimum small size and light weight for this critical
airborne RF radar system. Flip Chips were first used by IBM in mainframe computers in the 1960’s and by Delphi Electronics in Antilock Braking Systems in 1985. As the aircraft ages, this RF radar asset will be upgraded by current EMPF/Raytheon partnership whose goal is to optimize the manufacturing processes for these chips.

These three examples underscore the need for sustainment as well as upgrade of RF systems and the role of the EMPF in each.

1. David B. Cotton “Will Software Radio Become Real – And When?” COTS Journal, Vol. 6 No.1, January 2004, pg. 29