# Military Communications Conference, 1989. MILCOM '89. Conference Record. Bridging the Gap. Interoperability, Survivability, Security., 1989 IEEE

## Filter Results

Displaying Results 1 - 25 of 169
• ### Adaptive HF for voice and data

Publication Year: 1989
| | PDF (42 KB)

Summary form only given. The authors describe an adaptive HF system for voice and video. The system uses information obtained from a link quality analysis and/or ionospheric soundings to determine the appropriate link and frequency over which to communicate. In addition, the system can be frequency hopped, thereby reducing the probability of being jammed. The improved performance obtained using fr... View full abstract»

• ### MILCOM 89. Bridging the Gap. Interoperability, Survivability, Security. Conference Record. 1989 IEEE Military Communications Conference (Cat. No.89CH2681-5)

Publication Year: 1989
| PDF (157 KB)
• ### A connection between Rayleigh fading and worst-case partial band interference

Publication Year: 1989, Page(s):693 - 696 vol.3
Cited by:  Papers (2)
| | PDF (256 KB)

For FH/BFSK (frequency hopping/binary frequency-shift keying) on a worst-case partial-band Gaussian interference channel, the bit error probability results are well known for the extreme cases in which the signal is either nonfading or Rayleigh fading. In the present work the author fills in the region between these extremes by considering the general Nakagami-m fading model. Here the wor... View full abstract»

• ### An approach to loading analysis for ECCM networks operating in a hardlimiting transponder

Publication Year: 1989, Page(s):452 - 456 vol.2
Cited by:  Papers (1)
| | PDF (304 KB)

The authors present a novel approach for determining the required uplink EIRP (effective isotropically radiated power) for each link of an ECCM (electronic counter countermeasures) satellite communications network as a function of link and network parameters. A feature of this analysis is that each link can be assigned a parameter that indicates the fraction of transponder capacity required by tha... View full abstract»

• ### The performance of a CPFSK trellis code in non-Gaussian noise

Publication Year: 1989, Page(s):769 - 773 vol.3
Cited by:  Papers (1)
| | PDF (344 KB)

Recently R. Padovani and J.K. Wolf (IEEE Trans. Commun., vol.COM-34, no.5 p.446-53, May 1986) extended the Ungerboeck class of trellis codes to signal sets based on combined PSK (phase-shift-keying) and FSK (frequency-shift-keying) modulation (CPFSK). This class of codes has important advantages in the LF and VLF bands, where bandwidth is very scarce and the available transmitter hardware is intol... View full abstract»

• ### Performance of fast frequency hopped noncoherent MFSK with a fixed hop rate under worst case jamming

Publication Year: 1989, Page(s):30 - 36 vol.1
Cited by:  Papers (1)
| | PDF (492 KB)

The authors evaluate the throughput performance of FFH/MFSK (fast frequency hopping/M-ary frequency-shift keying) with a fixed hop rate for both uncoded and coded systems. The performance criterion used is a throughput measure, that is information rate sustained by a system for a given bit-error rate normalized by the hop rate. It is shown that the performance can be greatly improved thro... View full abstract»

• ### Throughput optimization in single commodity slotted ALOHA multi-hop packet radio networks

Publication Year: 1989, Page(s):377 - 382 vol.2
Cited by:  Papers (1)
| | PDF (396 KB)

The authors investigate the maximum throughput that can be supported between a pair of nodes in a multihop packet radio network using slotted ALOHA. The optimization problem can be formulated as a nonlinear programming problem. The authors study different topologies where source and destination are connected with a number of independent paths and consider the cases in which the flow from source to... View full abstract»

• ### Truncation effects in Viterbi decoding

Publication Year: 1989, Page(s):541 - 545 vol.2
Cited by:  Papers (10)  |  Patents (2)
| | PDF (288 KB)

Practical Viterbi decoders often fall significantly short of full maximum likelihood decoding performance because of survivor truncation effects. In the present work the authors study the tradeoff between truncation length and performance loss for the two most common variations of Viterbi's algorithm: best-state decoding (BSD) and fixed-state decoding (FSD). It is found that FSD survivors should b... View full abstract»

• ### A new path metric for survivable circuit switched routing

Publication Year: 1989, Page(s):688 - 692 vol.3
Cited by:  Papers (5)  |  Patents (3)
| | PDF (360 KB)

The authors report a novel path metric for survivable circuit switched routing. The distribution of physical assets in the network is assumed flat, and the network operates in a stressed environment with link and node failures. In addition, the traffic distribution is arbitrary as a function of space and time. The fundamental assumption driving this work is that delay', both processing delay at a... View full abstract»

• ### Performance of a lightweight, low-cost geostationary X-band MILSATCOM

Publication Year: 1989, Page(s):445 - 451 vol.2
| | PDF (380 KB)

The authors describe a payload concept for a new class of X -band satellites to supplement current X-band MILSATCOMs. The design exercise seeks to show that substantial communications capacity may be provided in a small, easily proliferated payload put into geostationary orbit to supplement existing and planned satellites without changing the ground segment. The concept presented... View full abstract»

• ### The use of linear prediction filters in square law detection of covert signals

Publication Year: 1989, Page(s):289 - 293 vol.1
| | PDF (312 KB)

The author considers the performance of a square law detector for direct sequence spread spectrum binary phase shift keying (DSSS-BPSK) signals in the presence of broadband interference when filtering is employed to excise the interference. A linear predictive filter operating at steady state is considered as the excision filter. It is demonstrated that large gains can be achieved by the use of pr... View full abstract»

• ### An automatic high frequency radio network for the Military Airlift Command

Publication Year: 1989, Page(s):90 - 94 vol.1
Cited by:  Papers (2)
| | PDF (336 KB)

The authors describe the initial design of an automatic high-frequency (HF) radio network for the Military Airlift Command (MAC). The network design incorporates new technology that will make HF communications more reliable. The network uses the Automatic Communications processor (ACP) developed for MAC to perform adaptive frequency selection and automatic link establishment (ALE). The MAC network... View full abstract»

• ### A computer simulation analysis of conventional and trunked land mobile radio for a system with a small number of user groups

Publication Year: 1989, Page(s):923 - 927 vol.3
Cited by:  Patents (1)
| | PDF (376 KB)

Trunked land mobile radio (LMR) systems, currently being developed by several companies, allow many groups of LMR users to share a set of channels dynamically, reducing the total number of channels needed to support these groups. These systems also support dynamic regrouping, reassigning individual users to different groups through software in the controlling computer. The authors discuss a comput... View full abstract»

• ### Cutoff rate for channel having precoding, continuous-phase modulation, and differential detection

Publication Year: 1989, Page(s):764 - 768 vol.3
Cited by:  Papers (2)
| | PDF (324 KB)

The authors consider encoded M-ary continuous-phase-modulated signaling with suboptimal demodulation-decoding, a transmission scheme useful when bandwidth and power are limited. Demodulation is via differential detection, and decoding is optimal. It is assumed that additive white Gaussian noise is the only disturbance. A form of precoding that undoes, before it is done, the correlation am... View full abstract»

• ### GaAs in the military marketplace

Publication Year: 1989, Page(s):122 - 127 vol.1
| | PDF (432 KB)

It is noted that, with the advantages (speed and low power) of using GaAs digital integrated circuits, GaAs has now become the technology of choice for high-performance systems. Over the past three years, improvements in processing, manufacturing, and design methodology have been able to overcome the major barriers to the acceptance of this technology, that is yield, cost, stable sources of supply... View full abstract»

• ### Performance of Viterbi's ratio threshold receiver against mixed jamming

Publication Year: 1989, Page(s):25 - 29 vol.1
Cited by:  Papers (2)
| | PDF (200 KB)

A performance analysis is presented for a coded FH/MFSK (frequency-hopping/M-ary frequency-shift-keying) system under a combination of tone jamming and full-band-noise jamming (FBNJ). A maximum likelihood metric former with Viterbi's ratio threshold techniques is assumed to support the decoder in the system. It is shown that the most efficient FBNJ portion of the total jamming power depen... View full abstract»

• ### A technique for detecting unknown weak signals in noise that is not additive white Gaussian

Publication Year: 1989, Page(s):370 - 376 vol.2
Cited by:  Papers (12)
| | PDF (376 KB)

A general spectrum-analysis-based approach to the problem of detecting the presence of unknown weak signals in noisy observations is developed. The weak signal assumption enables exploitation of familiar results from the theory of local optimality, from which correlation-based detectors for the presence of known weak signals in additive independent and identically distributed (IID) noise have been... View full abstract»

• ### 8-PSK trellis codes on Rayleigh channel

Publication Year: 1989, Page(s):536 - 540 vol.2
Cited by:  Papers (8)  |  Patents (1)
| | PDF (276 KB)

Trellis-coding techniques are considered as a means of improving the reliability of 8-PSK (phase-shift keying). It is shown that the combination of a rate 2/3 convolution code and 3-b interleavers provides a good modulation/coding method for the Rayleigh channel. The author proposes a suboptimal coded system that combines a regular convolutional code, bit interleaving, and an appropriate decoding ... View full abstract»

• ### A distributed multiple media network architecture

Publication Year: 1989, Page(s):784 - 788 vol.3
Cited by:  Papers (11)  |  Patents (4)
| | PDF (456 KB)

The Media Resource Controller (MRC) project was initiated to develop an advanced development model (ADM) testbed to be used in the evaluation of reconstitutable network control techniques using multiple-media point-to-point radio links. The planned operational application of this technology is to the 21st century tactical air control system. The ADM MRC was required to integrate three distinct poi... View full abstract»

• ### Value-based multiplexing of time-critical traffic

Publication Year: 1989, Page(s):395 - 401 vol.2
Cited by:  Papers (5)
| | PDF (556 KB)

The concept of message value' is used as a means of measuring performance. A `value function' is defined for each message and represents its value to the intended recipient as a function of the total delay in transporting it. These value functions not only incorporate the usual notions of relative priority (i.e. importance) between different messages but also capture the time-critical characteris... View full abstract»

• ### Adaptive rate error control through the use of diversity combining and majority logic decoding in a hybrid-ARQ protocol

Publication Year: 1989, Page(s):558 - 563 vol.2
Cited by:  Papers (1)  |  Patents (2)
| | PDF (368 KB)

The author demonstrates an adaptive rate coding system based on the majority logic decoding of convolutional codes. The proposed system retains the high-data-rate capability of FEC (forward error correction) majority logic decoders while providing an adaptive code rate and a significant improvement in error protection through the incorporation of diversity combining and hybrid-ARQ (automatic repea... View full abstract»

• ### A frequency-hopped MFSK communication system for multiple access

Publication Year: 1989, Page(s):139 - 143 vol.1
| | PDF (276 KB)

A modified receiver for frequency-hopped MFSK (M-ary frequency-shift keying) for mobile communications is presented. This modified receiver provides an implementation advantage by eliminating unnecessary energy detection of all the frequency channels. A performance analysis of the proposed system is carried out by using the union bound. It is shown that an optimum number of message bits f... View full abstract»

• ### Automatic modulation recognition of digitally modulated signals

Publication Year: 1989, Page(s):645 - 649 vol.3
Cited by:  Papers (37)  |  Patents (1)
| | PDF (364 KB)

A modulation recognizer that automatically reports modulation types of constant-envelope modulated signals is developed using zero-crossing techniques. The zero-crossing sampler, as a signal conditioner, has the advantage of providing accurate phase transition information over a wide dynamic frequency range. Signal parameters, such as zero-crossing variance, carrier-to-noise ratio (CNR), and carri... View full abstract»

• ### Enhanced network survivability through balanced resource criticality

Publication Year: 1989, Page(s):682 - 687 vol.3
Cited by:  Papers (6)  |  Patents (9)
| | PDF (356 KB)

The authors describe two entropy-based measures that can be used to assess how close a network design comes to being maximally survivable: normalized node entropy (NNE) and normalized link entropy (NLE). Maximum survivability is achieved when the enemy cannot identify critical points of failure and must remove a maximum number of nodes/links before the network becomes disconnected. The normalized ... View full abstract»

• ### Consistent estimation models for the fine time synchronization of FH systems

Publication Year: 1989, Page(s):895 - 899 vol.3
Cited by:  Papers (9)  |  Patents (1)
| | PDF (320 KB)

Four basic estimation methods are discussed, namely the delay-advance method, the early-late filter method, a modified early-late filter method, and the novel two-tone method. These methods all use noise power estimation in a frequency bin not occupied by a signal; this estimate is then used to reduce the bias and make the estimate of the time error consistent. Simulation results on the performanc... View full abstract»