Military Sector View

Military Sector View
Radio communications has been an important part of the operations of military forces
for many decades. A prominent example is the walkie-talkie radio, developed by
Motorola and used extensively by U.S. soldiers beginning in World War II. The walkietalkie
evolved into a more modern system called a net-broadcast radio system, in which
a user can talk with any other individual user in a defined group or talk simultaneously
to a number of users tuned to the same frequency channel. As communications
technology advanced, the military saw a need for antijamming (A/J) communications
capability, to thwart various forms of deliberate interference with transmitted signals.
Beginning in the 1950s, the defense communications industry invested a great amount
of effort in research and development on concepts and systems for A/J communications.
A key technique central to these developments was spread-spectrum communications,
employing various forms of direct-sequence or frequency-hopped transmission.
A closely related development was that of code-division multiple access (CDMA),
allowing multiple users to have simultaneous access to a communication channel with a
controllable amount of user-to-user interference. For many years, the spread-spectrum
and CDMA technologies were considered to be too expensive for use in commercial
communications systems, but the ongoing advances in microelectronics and the
economies of scale achieved in commercial product manufacturing eventually brought
these technologies down to price points that made them feasible for use in commercial
communications systems. Given this background, in the early 1990s Qualcomm
Corporation developed a digital cellular system based on spread-spectrum signaling
and CDMA and proposed this design as a new standard for digital cellular telephone
communications. The design was subsequently adopted as the IS-95 standard and is
now the predominant cellular telephone technology in the United States.
Along with A/J capability, military forces have always had a critical need for information
security in all modes of communication, including wireless networking. This
motivated research over many decades in cryptographic techniques for protecting transmitted
information. Commercial versions of military cryptographic techniques have
thus been adopted in digital cellular networks and into WLAN products as well.
Other wireless communications techniques developed to meet the needs of military
operations are also finding their way into commercial system developments. One
example is ad hoc networking, aimed at meeting the military need for reliable communication
connectivity with steadily increasing degrees of mobility in combat operations.
Along with the evolution of military connectivity and mobility requirements, we see
requirements for integration of geolocation awareness into military communications
systems. Another system concept developed for the military in recent years is that of
the body LAN or wearable LAN, in which wireless LAN devices are integrated into a
soldier’s uniform and into the equipment the soldier carries in a combat environment.
Wireless communication between these embedded devices and between the devices and
a fixed network can be used to support tactical operations as well as medical operations
when soldiers are wounded in battle.
Another important development is the use of space-time coding, offering further
advances in reliability and capacity in wireless communications networks. Thus, we
can expect to see a continuation of new wireless systems concepts and techniques,
motivated by stringent military communications requirements, eventually migrating
into affordable commercial network technologies