Pub Date : 1992-10-11DOI: 10.1109/MILCOM.1992.243963
R. Prill, M. Antonesco
The authors describe ongoing work by GEC-Marconi Electronic Systems Division in the development of a multifunction, common module, programmable digital radio/modem. The radio system handles both conventional narrowband and spread-spectrum waveforms. The architecture developed is a programmable channelized approach. In the channelized approach the modules of one channel are identical to those of the next, and as such are ideally suited to channel reusability during different parts of a mission or during failure modes of higher-priority functional systems. The hardware implementation exploits the latest RF, digital-RF, and digital signal processing component technologies. A PC-based brassboard was developed and used to demonstrate real-time programmable AM, FM, and IFF reception.<>
{"title":"Programmable channelized digital radio/modem","authors":"R. Prill, M. Antonesco","doi":"10.1109/MILCOM.1992.243963","DOIUrl":"https://doi.org/10.1109/MILCOM.1992.243963","url":null,"abstract":"The authors describe ongoing work by GEC-Marconi Electronic Systems Division in the development of a multifunction, common module, programmable digital radio/modem. The radio system handles both conventional narrowband and spread-spectrum waveforms. The architecture developed is a programmable channelized approach. In the channelized approach the modules of one channel are identical to those of the next, and as such are ideally suited to channel reusability during different parts of a mission or during failure modes of higher-priority functional systems. The hardware implementation exploits the latest RF, digital-RF, and digital signal processing component technologies. A PC-based brassboard was developed and used to demonstrate real-time programmable AM, FM, and IFF reception.<<ETX>>","PeriodicalId":394587,"journal":{"name":"MILCOM 92 Conference Record","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130728439","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1992-10-11DOI: 10.1109/MILCOM.1992.244092
N. Stojanović, V. Jovanovic
Threshold setting methods for serial search acquisition of frequency hopping waveforms are considered. The reference channel detector (Stojanovic and Jovanovic, 1991), which shows considerable immunity to charges in signal dynamics and pulse jamming, is analyzed with respect to hardware complexity. Various configurations are discussed, and their performance is evaluated. A modified search strategy which reduces the mean acquisition time is proposed. For slow frequency hopping, it is shown that a widely used procedure in tactical radios, where a binary demodulator is followed by a correlator, is the direct approximation of the reference channel detector.<>
研究了跳频波形串行搜索采集的阈值设置方法。参考信道检测器(Stojanovic and Jovanovic, 1991)在信号动力学和脉冲干扰中表现出相当大的抗电荷性，从硬件复杂性方面进行了分析。讨论了各种配置，并对其性能进行了评估。提出了一种改进的搜索策略，减少了平均获取时间。对于慢跳频，战术无线电中广泛使用的一种方法是直接逼近参考信道检测器，即在二进制解调器后面跟着一个相关器。
{"title":"On the practical aspects of the reference channel detector in frequency-hopping receivers","authors":"N. Stojanović, V. Jovanovic","doi":"10.1109/MILCOM.1992.244092","DOIUrl":"https://doi.org/10.1109/MILCOM.1992.244092","url":null,"abstract":"Threshold setting methods for serial search acquisition of frequency hopping waveforms are considered. The reference channel detector (Stojanovic and Jovanovic, 1991), which shows considerable immunity to charges in signal dynamics and pulse jamming, is analyzed with respect to hardware complexity. Various configurations are discussed, and their performance is evaluated. A modified search strategy which reduces the mean acquisition time is proposed. For slow frequency hopping, it is shown that a widely used procedure in tactical radios, where a binary demodulator is followed by a correlator, is the direct approximation of the reference channel detector.<<ETX>>","PeriodicalId":394587,"journal":{"name":"MILCOM 92 Conference Record","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128999622","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1992-10-11DOI: 10.1109/MILCOM.1992.243956
J. Agrawal, U. Varshney
The design of a multimedia LAN (MLAN) protocol using a broadcast bus system topology suitable for a campus environment is considered. It minimizes the bus access time by using an advanced reservation technique, and accommodates requests for several packet sizes expressed in multiples of asynchronous transfer mode (ATM) cell size. The architecture presented assumes a MLAN speed of 50 Mb/s, and can be easily extended to the STS-3 signal bit rate of 150 Mb/s. The bus access techniques, bandwidth allocation for various types of traffic, clock synchronization, etc. are monitored and changed/adjusted dynamically according to traffic conditions on the bus.<>
{"title":"A dynamic high speed multi-media local area network (MLAN) protocol architecture","authors":"J. Agrawal, U. Varshney","doi":"10.1109/MILCOM.1992.243956","DOIUrl":"https://doi.org/10.1109/MILCOM.1992.243956","url":null,"abstract":"The design of a multimedia LAN (MLAN) protocol using a broadcast bus system topology suitable for a campus environment is considered. It minimizes the bus access time by using an advanced reservation technique, and accommodates requests for several packet sizes expressed in multiples of asynchronous transfer mode (ATM) cell size. The architecture presented assumes a MLAN speed of 50 Mb/s, and can be easily extended to the STS-3 signal bit rate of 150 Mb/s. The bus access techniques, bandwidth allocation for various types of traffic, clock synchronization, etc. are monitored and changed/adjusted dynamically according to traffic conditions on the bus.<<ETX>>","PeriodicalId":394587,"journal":{"name":"MILCOM 92 Conference Record","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121162041","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1992-10-11DOI: 10.1109/MILCOM.1992.244102
W. Ralston, J. Weitzen
By using the diversity factor as a measure of the link correlation in a meteor-burst communications system, performance bounds for the network waiting time of meteor burst networks are found. It is shown that the performance of a meteor burst network can degrade significantly when the diversity factor is low unless a means of processing multiple responses per trail is provided. A code-division multiple-access system is shown to be one means of providing and allocating additional capacity for processing multiple responses. Significant reductions in the waiting time of the system are obtained.<>
{"title":"Network waiting time for meteor-burst communications","authors":"W. Ralston, J. Weitzen","doi":"10.1109/MILCOM.1992.244102","DOIUrl":"https://doi.org/10.1109/MILCOM.1992.244102","url":null,"abstract":"By using the diversity factor as a measure of the link correlation in a meteor-burst communications system, performance bounds for the network waiting time of meteor burst networks are found. It is shown that the performance of a meteor burst network can degrade significantly when the diversity factor is low unless a means of processing multiple responses per trail is provided. A code-division multiple-access system is shown to be one means of providing and allocating additional capacity for processing multiple responses. Significant reductions in the waiting time of the system are obtained.<<ETX>>","PeriodicalId":394587,"journal":{"name":"MILCOM 92 Conference Record","volume":"93 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121697528","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1992-10-11DOI: 10.1109/MILCOM.1992.244006
S. Howard
The performance of fast Fourier transform (FFT)-based excision processing (suppression of narrowband interference collocated in frequency with direct-sequence spread-spectrum signals) using block sizes which have time durations less than a bit time is examined. The FFT block size is chosen to provide frequency resolution consistent with the interference environment, and it is smaller than the number of samples taken during the data bit period. This technique is favorable in situations where the interference is sparse and the processing gains are large. Rectangular windowing with nonoverlapped processing and Hann and Hamming windowing with 50% overlapped processing are compared. Results for single continuous wave interference signals at jammer-to-signal ratios of 0 to 100 dB are presented. The performance for this method of processing is comparable to that for systems where the block size is coincident with the data bit duration, but the processing load has been reduced.<>
{"title":"Narrowband interference rejection using small FFT block sizes","authors":"S. Howard","doi":"10.1109/MILCOM.1992.244006","DOIUrl":"https://doi.org/10.1109/MILCOM.1992.244006","url":null,"abstract":"The performance of fast Fourier transform (FFT)-based excision processing (suppression of narrowband interference collocated in frequency with direct-sequence spread-spectrum signals) using block sizes which have time durations less than a bit time is examined. The FFT block size is chosen to provide frequency resolution consistent with the interference environment, and it is smaller than the number of samples taken during the data bit period. This technique is favorable in situations where the interference is sparse and the processing gains are large. Rectangular windowing with nonoverlapped processing and Hann and Hamming windowing with 50% overlapped processing are compared. Results for single continuous wave interference signals at jammer-to-signal ratios of 0 to 100 dB are presented. The performance for this method of processing is comparable to that for systems where the block size is coincident with the data bit duration, but the processing load has been reduced.<<ETX>>","PeriodicalId":394587,"journal":{"name":"MILCOM 92 Conference Record","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128038307","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1992-10-11DOI: 10.1109/MILCOM.1992.243940
J. Yoo
A computer simulation has shown that a modified chirp filter with odd phase symmetry can suppress the line spectrum produced by a binary phase shift keying (BPSK) signal at the output of a squaring circuit (SC) by destroying the cyclostationarity of the signal. Unlike LPI waveform shaping by heavy filtering, the modified chirp filter converts the line spectrum to the self-noise spectrum. This line spectrum can be restored using a matched filter. However, the advantage of using the modified chirp filter over an ordinary chirp filter is the difficulty of figuring out its matched filter even if the chirp duration and frequency slope are known to the interceptor.<>
{"title":"LPI waveform shaping by modified chirp filter","authors":"J. Yoo","doi":"10.1109/MILCOM.1992.243940","DOIUrl":"https://doi.org/10.1109/MILCOM.1992.243940","url":null,"abstract":"A computer simulation has shown that a modified chirp filter with odd phase symmetry can suppress the line spectrum produced by a binary phase shift keying (BPSK) signal at the output of a squaring circuit (SC) by destroying the cyclostationarity of the signal. Unlike LPI waveform shaping by heavy filtering, the modified chirp filter converts the line spectrum to the self-noise spectrum. This line spectrum can be restored using a matched filter. However, the advantage of using the modified chirp filter over an ordinary chirp filter is the difficulty of figuring out its matched filter even if the chirp duration and frequency slope are known to the interceptor.<<ETX>>","PeriodicalId":394587,"journal":{"name":"MILCOM 92 Conference Record","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122771980","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1992-10-11DOI: 10.1109/MILCOM.1992.244111
E. W. Jacobs, R. D. Boss
A review of iterated transformation image compression is presented. Generalization of simple iterated function system fractal generating algorithms to an automated iterated transformation algorithm used to compress gray-scale images is reviewed. Compressed images from the Digital Terrain Elevation Database (DTED) are presented and are compared with encodings using adaptive discrete cosine transformations and mean residual vector quantization image compression techniques.<>
{"title":"Fractal image compression using iterative transforms: applications to DTED","authors":"E. W. Jacobs, R. D. Boss","doi":"10.1109/MILCOM.1992.244111","DOIUrl":"https://doi.org/10.1109/MILCOM.1992.244111","url":null,"abstract":"A review of iterated transformation image compression is presented. Generalization of simple iterated function system fractal generating algorithms to an automated iterated transformation algorithm used to compress gray-scale images is reviewed. Compressed images from the Digital Terrain Elevation Database (DTED) are presented and are compared with encodings using adaptive discrete cosine transformations and mean residual vector quantization image compression techniques.<<ETX>>","PeriodicalId":394587,"journal":{"name":"MILCOM 92 Conference Record","volume":"54 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122833013","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1992-10-11DOI: 10.1109/MILCOM.1992.244050
J. T. Gamble
The author analyzes the flat-fading-channel performance of coherent MSK (minimum shift keying) matched filter demodulation in the presence of cochannel interference. It is shown that the most deleterious interference is CW (continuous wave) at center frequency. Bit error rate (BER) performance is first characterized for nonfading signal and interference typical of a terrestrial line-of-sight scenario. Subsequent analyses address fading signal vs. nonfading interference (typical of a long skywave or scintillation communication path and local interference), fading signal vs. fading interference (typical of satellite communication performance in ionospheric fading and remote interference), and nonfading signal vs. fading interference. The performance under fading-signal conditions, regardless of whether the interference is constant (short range) or fading (long range), is extremely poor; to be usable, such channels will require the use of diversity techniques.<>
{"title":"MSK performance under various fading conditions in the presence of worst-case CW interference","authors":"J. T. Gamble","doi":"10.1109/MILCOM.1992.244050","DOIUrl":"https://doi.org/10.1109/MILCOM.1992.244050","url":null,"abstract":"The author analyzes the flat-fading-channel performance of coherent MSK (minimum shift keying) matched filter demodulation in the presence of cochannel interference. It is shown that the most deleterious interference is CW (continuous wave) at center frequency. Bit error rate (BER) performance is first characterized for nonfading signal and interference typical of a terrestrial line-of-sight scenario. Subsequent analyses address fading signal vs. nonfading interference (typical of a long skywave or scintillation communication path and local interference), fading signal vs. fading interference (typical of satellite communication performance in ionospheric fading and remote interference), and nonfading signal vs. fading interference. The performance under fading-signal conditions, regardless of whether the interference is constant (short range) or fading (long range), is extremely poor; to be usable, such channels will require the use of diversity techniques.<<ETX>>","PeriodicalId":394587,"journal":{"name":"MILCOM 92 Conference Record","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121765667","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1992-10-11DOI: 10.1109/MILCOM.1992.244024
J.M. McNulty
The author describes the modular translator display system (MTDS), a prototype system that is being developed to translate and display data from multiple tactical links. It is designed to be portable, modular, adaptable to existing systems, and extensible to future systems. The MTDS is a multiphase development whose design is object-oriented and utilizes multiple database objects to manage generalized track objects for link-to-link translations. Its database objects are implemented through the use of tailorable hashing functions that are capable of access times of the order of 1 mu s for MTDS Phase I DOS platforms.<>
作者描述了模块化翻译显示系统(MTDS)，这是一种正在开发的原型系统，用于翻译和显示来自多个战术环节的数据。它被设计成可移植、模块化、可适应现有系统，并可扩展到未来的系统。MTDS是一个多阶段的开发，其设计是面向对象的，并利用多个数据库对象来管理用于链接到链接转换的通用跟踪对象。它的数据库对象是通过使用可定制的哈希函数来实现的，对于MTDS Phase I DOS平台，这些哈希函数的访问时间大约为1 mu s
{"title":"Tactical data management in a multilink translator and display system","authors":"J.M. McNulty","doi":"10.1109/MILCOM.1992.244024","DOIUrl":"https://doi.org/10.1109/MILCOM.1992.244024","url":null,"abstract":"The author describes the modular translator display system (MTDS), a prototype system that is being developed to translate and display data from multiple tactical links. It is designed to be portable, modular, adaptable to existing systems, and extensible to future systems. The MTDS is a multiphase development whose design is object-oriented and utilizes multiple database objects to manage generalized track objects for link-to-link translations. Its database objects are implemented through the use of tailorable hashing functions that are capable of access times of the order of 1 mu s for MTDS Phase I DOS platforms.<<ETX>>","PeriodicalId":394587,"journal":{"name":"MILCOM 92 Conference Record","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133952340","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1992-10-11DOI: 10.1109/MILCOM.1992.243974
A. Dinc, Y. Bar-Ness
The authors extend the previously reported three structures of bootstrap blind adaptive separators to the multisignal channel case. They suggest a recursive weight updating algorithm for the three structures: power-power, correlator-correlator, and power-correlator. The optimum weights for these separators were found analytically in the absence of noise. The signal separation process was shown via simulation by the output learning curve. It was shown that the different bootstrap separators converge to their steady states almost with the same speed for a two or three signal channel. The steady-state interference residues of the three separators are different, lowest for power-power and highest for correlator-correlator. The use of equalization (automatic gain control) at the output of these structures improves the depth of interference cancellation dramatically.<>
{"title":"Convergence and performance comparison of three different structures of bootstrap blind adaptive algorithm for multisignal co-channel separation","authors":"A. Dinc, Y. Bar-Ness","doi":"10.1109/MILCOM.1992.243974","DOIUrl":"https://doi.org/10.1109/MILCOM.1992.243974","url":null,"abstract":"The authors extend the previously reported three structures of bootstrap blind adaptive separators to the multisignal channel case. They suggest a recursive weight updating algorithm for the three structures: power-power, correlator-correlator, and power-correlator. The optimum weights for these separators were found analytically in the absence of noise. The signal separation process was shown via simulation by the output learning curve. It was shown that the different bootstrap separators converge to their steady states almost with the same speed for a two or three signal channel. The steady-state interference residues of the three separators are different, lowest for power-power and highest for correlator-correlator. The use of equalization (automatic gain control) at the output of these structures improves the depth of interference cancellation dramatically.<<ETX>>","PeriodicalId":394587,"journal":{"name":"MILCOM 92 Conference Record","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1992-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134064110","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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