The efficiency of military presence of limited contingents in zones where a clash of interests takes place is primarily determined by command and control capabilities in the tactical echelon. Another crucial factor in this sense is the ability to maintain steady communications with the national military-political leadership. The diverse geographical location of seats of military conflicts practically leaves no alternative to satellite communications systems (SCS) as the main means capable of securing running communications that are independent of either topography or the spacing of relay satellites (RS), both mobile and fixed, in the radio-vision zone.

It is for this reason that the military satellite communications systems are of exceptional importance now--and likely to be even more so in the future--for ensuring stable governance of the Russian Federation power and governmental structures.

At the same time, a probe into the existing military satellite communications systems (ESSS-1 and first stage of ESSS-2) shows that they lack sufficient interference immunity and stability. This means they are morally and physically obsolescent in an environment characterized by intentional interference.

An integrated satellite communications system (ISSS-2) that is currently being developed on the basis of available R & D is devoid of the said defects and will possess a higher transmission capacity, this along with an ability to stand up in combat and an immunity to interference. ISSS-2 will establish stable, high-quality information highways for the benefit of the systems controlling the strategic and non-strategic nuclear forces, general-purpose forces of the RF AF, other troops and military units, as well as federal and regional government agencies under any conditions of the military-political situation, including in the face of pressure brought to bear by integrated reconnaissance and strike systems, anti-space warfare forces and electronic warfare suppression (EWS).

In peacetime ISSS-2 will provide high-quality satellite communication services to governmental and commercial users.

This program will make it possible to ensure inter-service standardization and a minimal range of satellite communicators for the RF AF. It will also help to rationalize the use of allocations for the development and deployment of ISSS.

The ISSS-2 program is due to become a component of a unified state and military governance system supposed to do the following: to secure interference-immune transmission and reception of orders from the centralized combat command and control of the strategic nuclear forces in peacetime and wartime during all periods of military-political situation; to organize interference-immune, secret telephony, telegraphy and phototelegraphy and data communications in the interests of all military C & C agencies of the RF AF, General Staff and staffs of the RF AF services, other military units, and federal authorities; to ensure interference immunity, cryptosecurity, and protection from an unauthorized use and interception of spacecraft control; to perform assigned missions in peacetime, during a conventional war, in emergencies, in the face of electronic countermeasures, and in an environment characterized by a potential adversary's purposeful counteraction.

The problem of ensuring SCS interference immunity and capacity is of scientific and technological nature, and therefore the level and degree of its solution depend at least on two groups of factors, scientific and technological. The scientific factors are methods of securing interference immunity of satellite radio links, resource control methods, methods of ensuring information communication efficiency, possible methods of electronic warfare suppression of information exchanges, models to study SCS characteristics amid intentional interference, as well as ways and means of technical realization as both anti-interference methods and EWS methods. The scientific factors define theoretically accessible characteristics of opposing parties in hypothetical conflict situations. Figuring importantly in this group are data on some promising vectors in investigations in the subject area under consideration that make it possible to forecast possible changes in the state of affairs and determine priorities in further R & D.

The specifics of the dedicated use of ISSS-2 implies a number of new emphases and restrictions in choosing a set of solutions determining the system's layout. Along with some sufficiently researched matters related to SCS functioning and control, there is a number of problems that are yet to be studied in depth. The most important problem in this category is how to make an efficient use of RS resources. Here we must mention low power supply, stringent restrictions on weight and bulk of specific equipment, low orientation and stabilization accuracy in orbit, and limited or nonexistent orbit adjustment opportunities.

We analyzed how to use RS resources efficiently and thereby to secure SCS interference immunity and operational efficiency. Our analysis shows that interference immunity and operational efficiency can be reached by several basic methods simultaneously.

In this context, such controversial things as interference immunity and transmission capacity can be addressed by both composite signals and adaptive selection methods.

Several main paths are suggested as a technological solution to the problem of ISSS-2 interference immunity and efficiency.

* First. A comprehensive use and rational combination of capabilities of the basic methods and devices to deal with the problem of SCS interference immunity and efficiency.

* Second. To use the circuitry and technological solutions that make it possible to produce multi-functional small-size devices performing several basic functions as a component of RS on-board equipment (search for composite signals, convolutions, filterings, weight ratio calculations, etc.)

* Third. To control RS resources and redistribute interference immunity and efficiency functions between basic devices depending on conditions of functioning and counteraction.

* Fourth. To use RS transmission capacity divided resource distribution methods as integrated with basic interference-immunity and adaptive selection methods.

Suppression of satellite repeaters is viewed as one of the most effective methods permitting to reduce combat efficiency of a number of military-technical systems. Repeaters are neutralized either by weapons or with the help of EWS.

Fire engagement has a limited effect because it is impossible to achieve instant suppression. Other limitations are considerable expenditures of fire resources to engage sensitive small-size targets, limited range of delivery vehicles, etc. In this connection, as held by the potential adversary, EWS is the most low-cost and simple and therefore most important (sometimes the only possible) method of bringing pressure to bear on SCS elements. In many cases, using EWS leads to the same consequences as physical destruction. The possibility of using EWS to suppress SCS elements points to the topicality of ensuring the needed level of interference immunity.

To increase ISSS-2 immunity, multi-satellite communications and control systems are recommended along with fixed-position RS. The former are composed of low-, middle- and high-orbit mobile RS, a circumstance that leads to the appearance of spatial dynamics in signal-interference situation.

The relative movement of repeaters and recipients will lead to a situation where the recipients that periodically vanish from the visibility zone of some RS will simultaneously appear in that of others. This imposes some stricter requirements on the promptness of establishing communications between repeaters and recipients. Thus, severe requirements are placed upon the make-up of on-board and ground signal-processing equipment, considering the environment in which ISSS-2 has to function. This environment is characterized by strict functional requirements, massive enemy employment of EWS, the use of code segmentation multiple access methods, spatial dynamics of relay satellites, etc.

Practically all the requirements are met by the combined processing systems (CPS), which is due to the use of several components that generally include polarizing, spatial, and temporal processing equipment and correlation processing devices.

Currently the CPS concept rests on a solid theoretical foundation. A theory for analyzing and synthesizing combined signal processing systems with interdependent adaptation has been developed that takes into account the resultant non-linear quality of targeted functions. This makes it possible to develop methods and algorithms of adaptation, and to evaluate CPS parameters and characteristics while tackling the utility reception problem against the background of combined interference.

Thus, the use of CPS at the physical level is capable of inducing higher efficiency in various application areas.

Col. V.A. GRIGORYEV (Ret.)

Doctor of Technical Sciences

Lt. Col. I.A. KHVOROV

Candidate of Technical Sciences