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- Ahlin, Lars, et al.
(författare)
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Automous Tactical Communications Possibilities and Problems
- 1997
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Ingår i: MILCOM 97 Proceedings. - 0780342496 ; , s. 393-397
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Konferensbidrag (refereegranskat)abstract
- In the battlefield of the future, more and more information will be available for making decisions on a tactical level, provided that this information can be dispersed rapidly and accurately. As a consequence, advanced tactical decision support that now is limited to advanced platforms (e.g. combat aircrafts) will become available at a much lower level, ranging from different kinds of vehicles, down to the individual soldier by means of ultra-light weight ``wearable'' equipment. Establishing reliable wireless communications in such a large group of users with unprecidented bandwidth demands and requirements on survivability constitutes a considerable enginerring challenge. In the paper we will, after a short review of some existing approaches, investigate the specific engineering challenges and the fundamental limitations of such low level, autonomous communication systems. Further we give an example of a system architecture, harmonized with a proposed structure for third generation commercial wireless systems (e.g. UMTS). Our conclusions show that mainly distributed computing complexity, device power consumption and available bandwidth constitute the fundamental problems.
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| 2. |
- Bark, Gunnar
(författare)
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Power control and active channel selection in an LPI FH system for HF communications
- 1997
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Ingår i: Proceedings of the 1997 MILCOM Conference. - : IEEE. - 0780342496 ; , s. 1031-1035
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Konferensbidrag (refereegranskat)abstract
- To improve the performance of frequency-hopping systems on interference-limited HF channels, so-called adaptive frequency-hopping (AFH), which uses an adaptively selected pool of the “best” hopping-frequencies for communication, has been proposed. We extend the adaptivity of the AFH scheme by adjusting the transmitted power on each channel individually and by adaptively changing the number Na of active channels that are selected to the pool. Fewer active channels (up to a certain point) give improved communication performance since the used channels, on the average, are less interfered. However, by decreasing Na, the protection against hostile detection is decreased. This trade-off between communication and LPI (low probability of intercept) performance with respect to Na is shown. Our analysis shows that the codeword error rate is minimized when about 20% of the channels are selected to the active pool, and that the LPI protection against the two tested hostile detectors, as expected, improves for larger Na. Generally, the hostile detectors require less received signal-to-interference ratio than the legal AFH receiver to obtain acceptable performance. For the parameters we have chosen in our duel simulation, the results indicate that the LPI performance seems to be more sensitive to the choice of active channel pool size than the communication performance.
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