Advancements in amplifiers allow military radios to reach further

Before the First World War, military forces attached radio antennas to kites to send them to the heights needed to get a signal and successfully transmit messages. However, adverse weather conditions, the inability to maintain a consistent height and the kite’s detectability often rendered this ineffective. Luckily, technology has come a long way since then.

Here David Reeves, International Director of Business Development at defence communications systems and battery specialist Ultralife, explains how these advances have helped to solve handheld, vehicular and military base communication challenges.

One of the main communication challenges that militaries across the globe have faced for over 100 years is loss of signal, which is often caused by being in an area with no radio coverage (known as dead spots). This can be extremely dangerous as it prevents soldiers from passing important messages to others in the field or those back at base. When this happens, soldiers can try to regain a signal by positioning the antenna in a higher location to improve line of sight. However, this is not always possible if one is close to an enemy position and needs to stay undetected. Therefore, another option is to try and increase the coverage range of the radio, so that it can communicate with devices outside of the dead spot.

Standard 5 W handheld military radios usually have an operating range of 8–10 km, depending on the ground and frequency they are operating on. Amplifiers, such as Ultralife’s A-320V3A, attach to the radio and can boost this distance by up to three times by increasing the wattage to 20.

If this still fails to reach another radio, then changing the radio frequency that is being used might provide a solution. This can be achieved by connecting an LNA adapter (such as Ultralife’s A-320DPA) to the amplifier, which allows a 30–108 MHz antenna and a 90–512 MHz antenna to be used without the need to keep removing and replacing them.

Both solutions have been widely proven to resolve coverage issues, making amplifiers an essential part of the modern soldier’s arsenal. However, amplifiers rely on a power source (such as a battery) to function. This is often separate to the radio’s internal battery but it must, nevertheless, meet the reliability and performance standards required for military use. Ultralife has its own well-established military battery manufacturing capabilities.

Choosing batteries for military communications equipment can be a challenge due to the demanding size, weight and power (SWaP) requirements. Military personnel need to minimise the amount of weight they carry and informed battery selection is a great way to achieve this. One of Ultralife’s UBI-2590 batteries (UBBL13-01) weighs only 1.45 kg but has a high energy density of 208 Wh/kg, which means it offers high power with a low weight, for effective communication and operation.

In addition to solving handheld radio communication problems, the military must also think about improving communications from within a vehicle. Vehicular radios have had a troubled past when it comes to SWaP. In 2012, the US stopped developing a vehicle-mounted version of the Joint Tactical Radio System (JTRS), as it was being produced to the size of a dormitory-sized refrigerator. Small size is paramount for vehicle radios and amplifiers as they may need to be removed for handheld use in ‘jerk and run’ scenarios or to be concealed to avoid detection.

Therefore, rather than having a radio and amplifier built specifically for a vehicle, it is common for soldiers to mount compact handheld radios and amplifiers into the vehicle, which also reduces having to carry separate radios and amplifiers when on foot. Ultralife offers several mounts, including one that can house both a radio and amplifier (A-320HVA) and another for the amplifier only (A-320QM).

Solving vehicle and on-foot communications is not the only issue however, as problems can also occur at the base camp. If the base is breached or the power is cut by the enemy, it is essential that communications equipment has backup power and can be easily transported to a new location. Unlike soldiers or vehicles, many base stations have access to AC/DC mains power supply. Ultralife’s LPAS-320U amplifier has been designed to utilise this, but also has a UBI-2590 battery fitted as a backup.

As you can see, amplifiers and batteries are paramount to solving today’s military communications challenges, providing covert, easy-to-carry solutions. It is hard to imagine the early days where kites were used. However, in an environment where enemies try to block or hinder communications, innovations such as those developed by Ultralife will be continually required to help militaries stay at the forefront.

Image credit: iStock.com/gorodenkoff