Troposcatter Communication Systems continue to provide a high value alternative to satellite systems for point-to-point high-bandwidth, low latency communications. This is reason enough for this very versatile and battle tested system to return as a redundant media for Beyond the Horizon Communication Systems

Chinese and Russian space surveillance networks are capable of searching, tracking, and characterizing satellites in all earth orbits. This capability supports both space operations and counter space systems. -US Defense Intelligence Agency, 11 Feb 2019

Balakot and the follow up standoff has indicated beyond doubt that, whatever be the Kinetic Energy platform used, secure and reliable communications will remain an essential and inescapable requirement for success. Multiple routing and redundancies will ensure reliability and real time round the clock capability to share information, exercise command & control and even guide weapons from standoff distances as it happened in Balakot.

Depending on a single media can lead to catastrophic failures. The Mirage aircrafts in the attack on Balakot were armed with Crystal Maze missiles and SPICE 2000 smart bombs. According to Indian Express Newspaper, the IAF wanted to use the Crystal Maze missiles to hit the targets but could not use it due to a heavy cloud cover over the region, which did not allow a direct line of sight to the pilots. Crystal Maze finds its target using Global Positioning System coordinates fed into it, then the pilot of the launching aircraft manually steers it using an electronic data-link between the aircraft and the weapon. The missile has the advantage of being more destructive and gives a live video feed of the weapon hitting its target. The SPICE 2000 provided an effective redundancy except the live video feed and was used successfully.

Redundancy during war therefore is not deleterious but beneficial; rather essential. Militaries are not like the industry in which cost cutting and efficiency leads to survival in competitive markets. In a competitive arena like ‘War’, no one can afford to be a runner up.

Communications in the Indian Subcontinent

The Indian Sub Continent is our Military’s playfield. The canvas is large and challenges of terrain on terrestrial communication networks are diverse and extreme. Notable terrain challenges are:

• Island territories; separated by a large expanse of water from the mainland.
• The Himalayan ranges in Jammu & Kashmir, Himachal Pradesh, Uttarakhand and Sikkim; rugged mountains with high passes which remain cutoff for a large part of the year.
• The vast and desolate desert of Rajasthan; the key to success in deserts is mobility.
• The width of Bangladesh separating Eastern states from the rest of India; restricts terrestrial communications to a narrow landmass in the Siliguri Corridor.
• The isolated valleys of Arunachal Pradesh; inter valley movement and communications are a big challenge.

The heart of the country has numerous OFC and microwave Network of Networks which provide adequate redundancy through alternate routing. The trouble begins at the forward edge in the above stated areas. Redundancy here is difficult to plan and configure; this condition in light of the Balakot example on redundancy is unacceptable. Any break in terrestrial communications will lead to an unmitigated disaster.

The biggest challenge for Modern Armies anywhere in the world in Tactical Battle Area (TBA) is Beyond the Horizon Communications (Without Multiple Relays). This achieved to a great extent using Microwave systems which however require a relay ever 25-35 Kms to extend communications beyond the horizon. Modern financial pundits see Satellites as a panacea to all the challenges of communicating beyond the horizon, over mountains and overseas. They are also being sold as the best means for inter thrust line and inter theatre communications.

It may however be noted that after the initial euphoria over satellite communications, technologists have started realizing that:

• Satellite once launched, requires to be monitored and controlled on regular basis so that it remains in the desired orbit.
• The strength and reception of a satellite signal is affected by weather or sunspots, take your mind to the blackout of television on a cloudy/rainy day.
• The average period of Propagation delay (latency) is between 500 and 900 milliseconds. This is tolerable when one simply needs basic Internet activities such as reading and sending e-mails. It is however too slow for military applications that require real-time access, such as video conferencing, VoIP telephone calls and sharing of large size operational data and information.
• Due to radio spectrum limitations, there is a fixed amount of bandwidth allocable to satellite transmission. Higher throughputs are promised but at astronomical cost per bit.
• Communication Satellites are vulnerable to malicious attacks that can intercept, manipulate, or block communications.
• Space robots can take control of the satellite or even destroy them. This can all happen with and without the use of kinetic weapons.
• There are No repair shops in space.

Threats from China will include Cyber Attacks against ground stations to damage tracking and Command & Control systems of the satellites. Jamming of satellite uplink and downlink signals using ground, air and space based jammers. And also destruction of satellites using ASAT missiles (Satellites cannot be easily camouflaged or hidden from the enemy). Even the superpowers are concerned.

Not surprisingly, nations are now actively testing methods to deny us continued use of space services during conflict. -General William Shelton, former commander of the U.S. Air Force Space

Recent Anti Satellite Events of Significance

• China successfully tested its ground-based direct-ascent anti-satellite (ASAT) missile in 2007. On May 2013, it also launched a longer-range missile simulating an ASAT flight profile all the way to near geosynchronous orbits.
• On 27 Mar 2019 India successfully launched the Ballistic Missile Defence Interceptor missile. This ASAT missile test called Mission Shakti engaged an Indian orbiting target satellite in Low Earth Orbit (LEO) in a ‘Hit to Kill’ mode.

The threat to Satellite Communication Systems is therefore is no longer speculative.

Communication satellites have been made a hot selling product even in our case despite the fact that the TBA is adjacent to our own land mass. There is very little likelihood of us engaging in a war against another country across the oceans, where in all probability like the western countries, satellites will have a principal role. Our rapid response system as proven post Balakot is an effective surveillance system across vast frontiers connected with Command and Control Systems and Weapon platform for real time engagement; a pan India terrestrial Network of Networks providing reliable Voice, Video and Data Communications backbone using OFC and Microwave links. Redundancy is provided through multiple routing and formation of grids. The challenge of an effective real time redundancy however lies in the underdeveloped and dangerous forward edge (TBA). This redundant media must not be restrictive on bandwidth and provide similar real time services as the backbone pan India Network.

Military Communication Satellites are unlikely to meet our complete redundancy requirements in war. I see lack of Beyond the Horizon Communications (without multiple relays) in the TBA as a ‘Pink Flamingo Event’ i.e a predictable but ignored event that can yield disastrous results.

What is the Solution?

The solution is a Troposcatter Communication System. The success of Mobile Troposcatter Systems in Op Enduring Freedom, Op Iraqi Freedom and Op Pawan has substantiated the value of Troposcatter communications for intra theatre and beyond a large geographical obstacle communications on the Modern Battlefield. Unlike Satellites, Troposcatter Systems handle large bandwidths and are able to support all modern requirements of Voice, Video and Data simultaneously and in real time.

What is Troposcatter?

It is a Beyond the Horizon (or Line of Sight) microwave communication technology that uses diffraction to achieve high bandwidth, low latency connectivity over the Horizon. The radio signals are refracted at the troposphere (the lowest atmospheric layer surrounding the earth) which contains humidity, precipitation and heat currents acting as enablers of the refraction. Troposcatter performs well in adverse atmospheric conditions and is ideal when deployed in mountainous regions.

Its nemesis came perhaps due to its large size and long set up and stabilization time. Arrival of the satellite and the early euphoria associated with it may have also helped.

All this has now changed and Tactical sized easily deployable Troposcatter Systems can provide large bandwidths and data rates over long distance. Solid State Amplifiers have replaced Tube amplifiers. Forward error correction and automated power control ensures systems that are smaller, faster, more reliable, and use less power.

It is for these reasons and due to vulnerabilities of satellites that Modern Armies are revisiting troposcatter communications technology for worldwide operations. Advantages are summarised as under:-

• Reliable in a wide variety of environmental conditions.
• Reduces or eliminates the need for communications relay sites for Beyond the Horizon Communications (without multiple relays).
• Works in rugged terrain.
• Automatically adjusts data rates due to atmospheric changes.
• Communicates IP voice, data messaging, and multimedia services simultaneously over ranges of at least 40 Kms.
• Now uses an easy-to-use graphic user friendly interface that is small, lightweight, and man-portable.
• It has many advantages which make it more effective than Satellite Communication Systems.

Evidently Troposcatter Communication Systems continue to provide a high value alternative to satellite systems for point-to-point high-bandwidth, low latency communications. This should be a sure reason for this very versatile and battle tested system to return as a redundant media for Beyond the Horizon Communication Systems. Satellite Communications Systems may continue to be used for communications with remote localities or overseas operations.