An advanced communications system for RF Armed Forces mobile formations.

As advances in science and technology enable constant improvements in the systems of weapons, combat and special equipment, the forms and methods of warfare are rapidly changing. The number of more complicated links between combined and ordinary units is growing and increasingly stringent requirements are imposed on command and control of troops. There are a growing number of tasks C & C is supposed to handle and of the amounts of input information needed for accomplishing them. Simultaneously, each C & C cycle is supposed to be completed in an appreciably shorter time. This imposes stricter standards on providing the commanders and staffs with stable, continuous, prompt and undetectable means of communication, increasing its protection, mobility and throughput capacity.

A modern communications system in support of military command and control agencies should be as a rule multichannel and broadband with a combined use of radio, microwave relay, troposcatter, satellite, wire, signaling and other facilities based on compression, switching and routing equipment, as well as the use of intelligent terminal transceiver devices.

Information exchange technologies that have come on the scene in recent years, such as VoIP, Wi-Fi, WiMAX, Bluetooth, DECT, IS-95 CDMA among many others, enable us to take a fresh look at the problems involved in the organization of communications in support of C & C agencies of different services and components of the RF Armed Forces.

This article suggests an advanced communications system for mobile formation of the RF Armed Forces taking account of their distinctive features.

To organize command and control of mobile formations of the RF Armed Forces, it is proposed to use the following types of communications: data transmission, e-mail, battle management digital telephone communications, command and conference-type C & C telephone communications and videotelephony.

During the period of their functioning, facilities controlling mobile formations can be in several modes: alert duty in various degrees of combat readiness in their permanent stationing locations, on the march, deploying (disbanding and dismantling) personnel and equipment, heightened alert in field positions.

Depending on the above modes, we can determine the following tasks of the communication system in support of combat management:

* organization of combat management communications, command-management and cross-aggregate communications using wire channels with control facilities at the places of permanent stationing;

* booking up wire channels which link signal centers of mobile formations' command posts to the Unified Communications Network of the Country using microwave relay lines;

* organization of radio communications with fixed-site and mobile C & C facilities on the march;

* provision of radio communications between field radio rooms (cross-aggregate communications) in the early periods of setting up and dismantling them in field positions;

* organization of command and management radio communications on the march, deployment, disbandment and dismantling of personnel and equipment in field positions;

* organization of communications channels between C & C facilities of mobile formations in field positions with the use of microwave relay links.

Now, what should an advanced system of technical assets integrated into the communications system of mobile formations look like to ensure high-quality performance of all its assigned tasks?

First, the entire network should be based on the principles of a single standardized backbone permitting a loss-free traffic generated by any terminal units.

Second, it is desirable that all elements of the communications system of mobile formations should support a unified data exchange protocol (IP batch transfer protocol, for example).

Third, the switching and routing facilities should support engines of different-priority data transfer from some or other terminals.

Fourth, the radio communications assets to be used should be built on the basis of adaptive radio technologies and they should be able to vary the power they emit and their carrier frequencies depending on the jamming situation and the wave propagation patterns in the frequency ranges they use.

Sixth, the advanced communications system should be based, if possible, on the equipment made by one and the same manufacturer, have a single automated control center, built-in monitoring facilities, a broad spectrum of supported terminal equipment and front ends for different signal propagation environments.

A block diagram of the advanced communications system of mobile formations of the RF Armed Forces can look as follows (see Figure).

There is a further range of specific requirements imposed on the communications system. It should support interaction between territorially dispersed segments of the local computer net of mobile formations. E-mail enables the transfer of messages between all the automated workstations of the persons in authority at the C & C facility equipped with client software and logged at the e-mail server.

[FIGURE OMITTED]

The videotelephony (audioconferencing) subsystem enables audio and narrow-band videoconferences for alert duty crews at the C & C facility.

The monitoring and management subsystem is needed for coordinating the resources and topology of the entire communications subsystem (both centralized and local), for displaying the condition of the hardware and for prompt alert to emergencies and malfunctions.

The power and life support subsystems are auxiliary subsystems to ensure that the system's hardware functions normally.

The command and management radio communications, when mobile formations are on the march or in the early periods of deployment (disbanding and dismantling) of the personnel and equipment, can be structured as a mini-cell radio net of the DECT or IS-95 CDMA standards providing combat teams with services of targeted voice messaging, data and picture transfer, and local audioconferencing. The DECT interface provides radio access and operates in the 1,880-, 900-MHz band and uses the multiple access principle and a time sharing duplex system. This interface makes possible to build channels of different capacity depending on the rate of digital data transfer.

However, the basic and terminal DECT devices currently in the market and offered by different manufacturing firms, do not fully meet the requirements imposed on military systems as to being resistant to temperatures and dynamic impacts. Furthermore, these devices should be additionally provided with scramblers to protect transmitted information. The IS-95 CDMA radio interface operating in the 800-1,900 MHz has been specially developed for user lines featuring all the advantages of digital switching technologies. But here again, we should design Russian equipment for this interface to meet the requirements imposed on military communications systems.

Russian developers of military communications systems should take notice of the new wireless networks IEEE 802.20 planned for production in 2006. The equipment supporting this standard enables a high rate of packet transmission (up to 1 mbps), enables mobile access to data from vehicles moving at speeds up to 250 kmh, it will make possible the necessary security levels of transmitted information and determine for every user, depending on its requirements and priorities, a corresponding throughput and QoS parameters. The equipment of this standard made by Russian manufacturers would meet as best as possible the requirements imposed on mobile command and management communications system of mobile formations.

We think that indispensable for the organization of cross-aggregate communications on the march and during the deployment of mobile formation are microwave relay equipment providing for a bandwidth wide enough to meet modern requirements and, of no less importance, making it scalable with no extra cost. We cannot overestimate this advantage of microwave relay stations when traffic grows continuously owing to the use in C & C processes of new information technologies. Already at the present time, the classical digital telephony calls for rates of 64 kbps both ways, data transfer in segments of local computer networks calls for between 128 kbps and 2 mbps, videoconference communications calls for 128 to 512 kbps both ways, and there is no knowing what rates would be needed for applications of tomorrow. Microwave relay stations handle with high effectiveness and as promptly as possible the tying in of signal centers of fixed-site and mobile C & C facilities to the Unified Communications Network of the Country.

Digital microwave relay stations that have replaced the earlier analogue stations are vastly different as regards their much enhanced data exchange capabilities, performance and design characteristics. They are much smaller and need less power to operate, which is of no small importance in employing them in rigorous conditions typical of mobile formations of RF Armed Forces.

The telecommunications services market currently features a great number of manufacturers of digital microwave relay equipment and naturally enough it is important to select equipment for the communications system appropriate to the missions of mobile formations of the RF Armed Forces. Analysis of this market enables a conclusion that practically all leading manufacturers of microwave relay stations make pieces equipment with very similar technical and user parameters. At the same time, the main provision in selecting equipment for signal centers and C & C facilities of the RF Armed Forces that remains in force is that this equipment should be Russian made. Such being the case, its parameters should also match those of international models.

Today there are several Russian manufacturers that meet these parameters. One possible example is the Scientific-technical Center (NTTs) NATEKS--a manufacturer of digital equipment for communications nets.

NTTs NATEKS has been in the business of designing radio equipment long enough, from the times of packet radio and packet controllers. It had quite a few successful projects in this field. Beginning in 2000, NATEKS started designing a microwave relay system of its own. It was designated Nateks-Microlink; the family of equipment includes both PDH and SDH approaches of Nateks Microlink-S and spans practically all of Russia's authorized bands and rates from 2 mbps to 155 mbps, or from one El stream to the SDH stream of STM1.

The many projects of recent years included the SDH line of 370 km in Tyumen, microwave relay lines in Baykonur, lines on railroads, in gas and oil industries and at various cellular communications operators. The main advantage of NTTs NATEKS equipment is a unified system of controlling it. If a PDH microwave relay line terminates in a multiplexer, this constitutes a unified control system with a multiplexer; if an SDH multiplexer is used at the termination of an SDH microwave relay line, a single control system is also used. Furthermore, the control system is compatible with any other piece of equipment, such as modems, flexible and optical multiplexers, etc. This makes it possible to build a sufficiently ramified network with the use of a variety of special devices.

Let us now look at the requirements imposed on the building of a unified standardized backbone for the communications system of mobile formations. Its main job consists in digitizing (analogue-to-digital conversion) of voice messages or images, compression and subsequent transmission with the use of some or other transfer technology and reverse conversion at the destination station. The encoding and compression engines are used to narrow the pass band required for multimedia traffic.

The primary requirements to be met in building such a backbone are: the efficient use of the channels; the provision of unified services on a single platform; the possibility of operation with the use of any communication channel that can be available; simplicity of control; the possibility of high rates of information exchange; open architecture allowing for the use of advanced network technology.

There are three main technologies that are used today to build multi-service backbones: the ATM technology, a technology using the Frame Relay (FR) technology, and a technology using the IP protocol.

ATM technology can be regarded as practically ideal for the building of multi-service backbones since it was developed specially for this purpose. Even so it has a number of drawbacks the biggest of which is that ATM equipment is complex and costly. Moreover, ATM technology has not been standardized for transfer rates below 2 mbps whereas such rates will be accessible and in demand in the communications system of mobile formations.

The FR transfer protocol and IP protocol, unlike ATM technology, were initially developed for data transfer alone and only later they were adapted with the aid of different configuration tools for handling heterogeneous traffics. Nonetheless, the technologies of building multi-service backbones based on the FR and IP protocols are practically fully standardized and are used in digital channels of between 64 and 2,046 kbps and even in analogue channels. The table below compares performance characteristics of IP- and FR-based technologies

Thus, these technologies have much in common, but each has its own advantages and drawbacks, that is to say, they are practically identical from the standpoint of the criteria listed earlier.

If we are to consider further aspects, we should pay attention to the following circumstance. The FR equipment market has been gradually shrinking since 1997 and some manufacturers either cut down on its production or farm it out to other companies. The market of equipment based on IP technology, on the contrary, is growing continuously. This is why the number of gadgets for multi-service nets operating on the H.323 standard is significantly greater today. Besides, terminal equipment for voice and picture transmission based on the H.323 standard is also very widely represented in the market place and it is, as a rule, compatible, which also helps make better choices. Thus, it is preferable in this connection to use IP technology equipment for the building of a unified backbone for the system of mobile formations.

It is worth noting that to make the RF Armed Forces C & C system comply with modern-day requirements, as military communications nets are developing, it is necessary to radically change the principles guiding the organization of communication. It is necessary to use digital communications channels instead of the switched communications nets that are being currently used. If it proves impossible to build or lease such channels, one should consider the option of using dedicated tone frequency channels. Specific technical approaches based on the already discussed features of the future communications net of TF Armed Forces mobile formations can be decided at the time of preliminary and detailed designing.

The suggested option for establishing an advanced communications system of RF Armed Forces mobile formations conforms with the concept of converting the communications system of the RF Armed Forces to digital modes of transferring and switching information developed by the staff of the chief of the RF Armed Forces signal service. The realization of the suggested approach will make it possible to integrate the advanced communications system of RF Armed Forces formations into the Unified Communications Network of the Country at minimal cost and close the considerable gap between the development of the special communications net and the development of general-use communications nets.

Col. V.A. Salin

Candidate of Technical Sciences

Performance Characteristics of IP- and FR-based Technologies

IP-based technology                FR-based technology

Operates on the third OSI (net)    Operates on the second OSI (channel)
layer                              layer
Operates in non-uniform nets       Requires uniform environment for its
                                   operation
Requires no prior connection       Requires prior connection
between users
Has engines of guaranteed          Presence of built-in and soft engines
standard of service on the         to provide guaranteed standard of
software level                     service
Second- and third-layer            Only second-layer housekeeping
housekeeping information added     information is added
Based on standard H.323 protocols  Standard FRE. 11/12 protocols
Convenient in administration,      More difficult to administrate,
does not require detailing         requires connections detailed
connections when topology and the  beforehand
number of users change
Enables operation using satellite  Enables operation using satellite
channels, including asymmetric     channels
channels