The first radios were substitutes for a pair of copper wires and were com-
monly referred to as wireless communications. These radios were used to
bridge gaps that couldn't be managed with wire lines, such as between ships at sea and the shore. Later, as FSK, facsimile, video, and encryption became popular, special purpose boxes were invented to encode and decode base band signals that were transmitted over these simple radio channels.

As the mobility of communications equipment became more and more important, the hardware in these external boxes were miniaturized and incorporated into the radios. The advent of powerful Digital Signal Processing (DSP) chips and controlling microprocessors enabled the very complex coding and modulation schemes described earlier in this handbook. These schemes have been used to increase the efficient use of bandwidth up to the point that is now approaching theoretical limits.

What challenges await military tactical radio communications equipment
in the 21st Century? The answer to this can be found by looking at the
changes that have emerged on the modern battlefield. During the Gulf War, we witnessed a dramatic increase in the operational tempo of the battlefield. Command and control communications were lost as the military forces moved rapidly across the flat desert terrain, outpacing the
conventional military communication systems. Increased information flow demands the use of data communications in place of voice communications, with an ever- increasing thirst for bandwidth. Critical battlefield
information must flow both horizontally and vertically, driving the need
for tactical networking.

There also emerges an increased need for situational awareness (SA) –
knowing the precise location of military assets and personnel. As force sizes are reduced through cuts in military spending, accurate situational
awareness is a key to maintaining the dominant level of force lethality. In
the future, SA will become a background task of the command and control
communications structure. Position information will be securely appended
to all voice and data traffic, and routed to a SA collection point so that
military commanders can plan and execute a successful military campaign.
Finally, increased sophistication of enemy forces will demand the use of
improved information security (INFOSEC) techniques. This includes stronger,
embedded encryption/ decryption devices used for all voice and data traffic, advanced electronic counter- counter measures (ECCM) methods to sustain communications in the presence of intentional jamming, and the use of Low- Probability of Intercept (LPI) and Low Probability of Detection (LPD) methods to protect forward- deployed troops operating in hostile areas.

Tactical Networking – Simple, Seamless and Secure Communications

During this past decade, we have all witnessed the impact the growth of the commercial Internet has had on countries around the globe. It demonstrates the power of seamless connectivity and the benefits gained from establishing common interfaces and protocols. Today the commercial Internet is starting to embrace the challenges presented by a wireless world. Many of these challenges are the same as those encountered in a modern military communications system – the demand for seamless connectivity, self- forming and healing networks, and secure communication links – to name but a few. Successful military communications equipment of the future will embrace this technology, building on the technological base established from enormous investments in the commercial sector.

Tactical networking will become an enabler for many military applications
in the 21st Century. Example applications include: command/ control systems; situational awareness systems; automatic range extension; tactical
messaging systems; fire- control systems; full duplex and simultaneous
voice/ data systems; common database access; even combat net radio
interface (CNRI) systems which link tactical and land- based infrastructures.

Radios, such as the Harris Falcon ™ II Tactical Radio Family, will provide
a seamless IP networking interface to other systems and application
programs. New systems will be quickly and cost- effectively developed using
commercial- off- the- shelf (COTS) tools and applications. Advanced channel access protocols are under development to ensure the maximum effective
use of the available frequency spectrum. Packet data transmissions will
enable multiple applications to be simultaneously supported on a priority-
driven basis and will allow voice and data traffic to coexist, even on a
single, narrowband radio channel.

Packet data transmission, combined with very fast receive- to- transmit
switching techniques, allow a simplex channel (one that alternately trans-
mits and receives on the same frequency) to emulate the performance of
full- duplex channels (one that receives and transmits on different frequencies simultaneously). It used to take two radios for retransmission, one to receive and the other to transmit simultaneously on another frequency.

Cutting edge radios of today can accomplish this with only one radio.

The trend in this area is to build a seamless network supporting any combi-
nation of point- to- point and point- to- multipoint voice and/ or data connections. Information will be encrypted and decrypted only at the origination and destination stations, ensuring information securing from end- to- end.

Higher Speed Data

During conflict, timely information collection and dissemination is critical to operating within the enemy’s decision cycle. This need for increased information flow is driving the desire for ever- increasing data transmission rates. The latest generation of tactical radios offers a 4x increase over those currently fielded. This increase in data rate significantly increases message throughput and reduces the message latency.
According to Chester Massari, Harris RF Communications division president, "Data transmission is the future of military communications. As one of the pioneers in this area, we can send high- speed imagery and data across the radio spectrum better than anyone in the industry – plus, we offer this capability for land, sea, and air missions."

Where Do We Go From Here?

It is natural to ask the question, where do we go from here? Of course,
with technology expanding at an ever- increasing rate, it is difficult to
predict specifics more than a year or so in the future, but these are some
of the important trends that are likely to influence radio technology
for many years to come.

As we said in the introduction to this handbook, "Stay tuned!"