Pub Date : 1982-10-01DOI: 10.1109/MILCOM.1982.4805979
R. Agustí, G. Junyent
This paper considers a Frequency Hopped Multilevel Frequency Shif Keying (FH-MFSK) spread spectrum communication system applied to mobile radio-telephony. We pre sent a mobile-to-base transmission model that allows to study system impairments, such as interference from nonsynchronous users and adjacent frequency channels in presence of matched tuned receiver filters. We have obtained results with mobile-to-base communication of 32 Kb/s per user in a 20 MHz (one-way) bandwidth. A bit error probability less than 10-3 can be maintained with up to 110 simultaneous users for practical average SNR ratio of 25 dB.
{"title":"Performance of a FH Multilevel FSK for Mobile Radio in the Presence of Nonsynchronous Users","authors":"R. Agustí, G. Junyent","doi":"10.1109/MILCOM.1982.4805979","DOIUrl":"https://doi.org/10.1109/MILCOM.1982.4805979","url":null,"abstract":"This paper considers a Frequency Hopped Multilevel Frequency Shif Keying (FH-MFSK) spread spectrum communication system applied to mobile radio-telephony. We pre sent a mobile-to-base transmission model that allows to study system impairments, such as interference from nonsynchronous users and adjacent frequency channels in presence of matched tuned receiver filters. We have obtained results with mobile-to-base communication of 32 Kb/s per user in a 20 MHz (one-way) bandwidth. A bit error probability less than 10-3 can be maintained with up to 110 simultaneous users for practical average SNR ratio of 25 dB.","PeriodicalId":179832,"journal":{"name":"MILCOM 1982 - IEEE Military Communications Conference - Progress in Spread Spectrum Communications","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1982-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131628774","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 : 1982-10-01DOI: 10.1109/MILCOM.1982.4805990
S. Alexander, J. Kauffman
The Least Mean Squares (LMS) algorithm has been frequently used for adapting the weighting multipliers of array elements which form the resulting antenna pattern. While significant performance gain has been reported for such applications as forming a pattern maximum in the direction of a desired signal and adaptively nulling strong jammers, many of the current results have assumed no mutual coupling between array elements. This paper examines the effects of mutual element coupling upon two properties of the LMS algorithm: (1) convergence rate, and (2) steady state pattern. Analysis is developed which displays the effects of mutual coupling explicitly via the elemental coupling coefficients. It is shown that both amplitude and phase of the elemental coupling in general degrades the convergence rate of the LMS algorithm and causes the pattern maximum to appear at a look-direction other than the angle of desired signal arrival. Several examples then illustrate LMS performance in representative coupled environments.
{"title":"Effects of Mutual Coupling upon the LMS Adaptive Antenna Array Algorithm","authors":"S. Alexander, J. Kauffman","doi":"10.1109/MILCOM.1982.4805990","DOIUrl":"https://doi.org/10.1109/MILCOM.1982.4805990","url":null,"abstract":"The Least Mean Squares (LMS) algorithm has been frequently used for adapting the weighting multipliers of array elements which form the resulting antenna pattern. While significant performance gain has been reported for such applications as forming a pattern maximum in the direction of a desired signal and adaptively nulling strong jammers, many of the current results have assumed no mutual coupling between array elements. This paper examines the effects of mutual element coupling upon two properties of the LMS algorithm: (1) convergence rate, and (2) steady state pattern. Analysis is developed which displays the effects of mutual coupling explicitly via the elemental coupling coefficients. It is shown that both amplitude and phase of the elemental coupling in general degrades the convergence rate of the LMS algorithm and causes the pattern maximum to appear at a look-direction other than the angle of desired signal arrival. Several examples then illustrate LMS performance in representative coupled environments.","PeriodicalId":179832,"journal":{"name":"MILCOM 1982 - IEEE Military Communications Conference - Progress in Spread Spectrum Communications","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1982-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130862148","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 : 1982-10-01DOI: 10.1109/MILCOM.1982.4805903
E. Hirshfield, M. Sites
As the prospect of full scale implementation of SSMA satellite communication systems approaches, methods will have to be developed to allow coexistence with other users employing different carrier modulations in a shared satellite transponder as well as graceful transition from a benign to stressed condition. The problem is magnified as communication density increases. This paper addresses a method for automatic control of the allocation of transponder resources to optimize throughput in accordance with user priorities and jamming level, and attempts to justify its use. The model employed assumes a mix of QPSK and direct sequence SSMA links. It also includes a simulation of system elements which can be used as a basis for accessing system capacity and exercising well-disciplined control to assure that the system delivers expected communication capacity.
{"title":"A Control Architecture for a Military SSMA Satellite Communication System","authors":"E. Hirshfield, M. Sites","doi":"10.1109/MILCOM.1982.4805903","DOIUrl":"https://doi.org/10.1109/MILCOM.1982.4805903","url":null,"abstract":"As the prospect of full scale implementation of SSMA satellite communication systems approaches, methods will have to be developed to allow coexistence with other users employing different carrier modulations in a shared satellite transponder as well as graceful transition from a benign to stressed condition. The problem is magnified as communication density increases. This paper addresses a method for automatic control of the allocation of transponder resources to optimize throughput in accordance with user priorities and jamming level, and attempts to justify its use. The model employed assumes a mix of QPSK and direct sequence SSMA links. It also includes a simulation of system elements which can be used as a basis for accessing system capacity and exercising well-disciplined control to assure that the system delivers expected communication capacity.","PeriodicalId":179832,"journal":{"name":"MILCOM 1982 - IEEE Military Communications Conference - Progress in Spread Spectrum Communications","volume":"69 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1982-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121193078","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 : 1982-10-01DOI: 10.1109/MILCOM.1982.4806018
E. J. Andrews, D. Holtzer, K. J. Gibson
Evolution of MILSATCOM terminals utilizing the EHF/SHF (40/20 GHz) frequency band places high demands on the terminal architecture and equipment design to provide required performance consistent with affordable life cycle costs. Factors influencing the terminal architecture and design include covert operation in the presence of a high jamming environment. These requirements are generally achievable only through the use of advanced technology concepts which are usually not consistent with low cost. The effort described in this paper was sponsored by RADC under Contract F30602-81-C-0154. It develops the interrelationship between terminal requirements, available technology and terminal architecture necessary to provide low life cycle cost terminals. An iterative process applied early in the design phase leads to the identification of high cost areas and through analysis and trade-off of technology, design and architecture, lower cost approaches are developed. Life-cycle analysis is accomplished through computer programs providing sensitivity data which is accurate and accountable for both design-to-unit-production-cost (DTUPC) and Life Cycle Cost (LCC).
{"title":"Low Life Cycle Cost EHF MILSATCOM Terminal Concepts","authors":"E. J. Andrews, D. Holtzer, K. J. Gibson","doi":"10.1109/MILCOM.1982.4806018","DOIUrl":"https://doi.org/10.1109/MILCOM.1982.4806018","url":null,"abstract":"Evolution of MILSATCOM terminals utilizing the EHF/SHF (40/20 GHz) frequency band places high demands on the terminal architecture and equipment design to provide required performance consistent with affordable life cycle costs. Factors influencing the terminal architecture and design include covert operation in the presence of a high jamming environment. These requirements are generally achievable only through the use of advanced technology concepts which are usually not consistent with low cost. The effort described in this paper was sponsored by RADC under Contract F30602-81-C-0154. It develops the interrelationship between terminal requirements, available technology and terminal architecture necessary to provide low life cycle cost terminals. An iterative process applied early in the design phase leads to the identification of high cost areas and through analysis and trade-off of technology, design and architecture, lower cost approaches are developed. Life-cycle analysis is accomplished through computer programs providing sensitivity data which is accurate and accountable for both design-to-unit-production-cost (DTUPC) and Life Cycle Cost (LCC).","PeriodicalId":179832,"journal":{"name":"MILCOM 1982 - IEEE Military Communications Conference - Progress in Spread Spectrum Communications","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1982-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124266753","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 : 1982-10-01DOI: 10.1109/MILCOM.1982.4805922
A. K. Elhakeen, H. Hafez, A. Ghafar
The worst case detectability is optimized with respect to the combined choice of the Spread Spectrum (SS) codes and receiver filters in a hard limited multi-access system. The multi-access repeater with a hard limiter will provide access to a group of n SS users, each employing pseudorandom (i.e. direct sequence DS) codes in the inphase (I) and quadrature (Q) channels of the offset Quadrature Phase Shift Keying OQPSK/DS system. Both like user interference and AWGN will be considered. Maximal linear codes, Gold, and Kassami codes of different lengths and raised cosine, Gaussian, Butterworth and Chebyshev band-pass filters of different shapes will form the set of the maximizing parameters.
{"title":"Optimal Codes and Filters for Hard-Limited OQPSK/DS Multiple Access Systems","authors":"A. K. Elhakeen, H. Hafez, A. Ghafar","doi":"10.1109/MILCOM.1982.4805922","DOIUrl":"https://doi.org/10.1109/MILCOM.1982.4805922","url":null,"abstract":"The worst case detectability is optimized with respect to the combined choice of the Spread Spectrum (SS) codes and receiver filters in a hard limited multi-access system. The multi-access repeater with a hard limiter will provide access to a group of n SS users, each employing pseudorandom (i.e. direct sequence DS) codes in the inphase (I) and quadrature (Q) channels of the offset Quadrature Phase Shift Keying OQPSK/DS system. Both like user interference and AWGN will be considered. Maximal linear codes, Gold, and Kassami codes of different lengths and raised cosine, Gaussian, Butterworth and Chebyshev band-pass filters of different shapes will form the set of the maximizing parameters.","PeriodicalId":179832,"journal":{"name":"MILCOM 1982 - IEEE Military Communications Conference - Progress in Spread Spectrum Communications","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1982-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124652999","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 : 1982-10-01DOI: 10.1109/MILCOM.1982.4805965
B. Levitt
The performance of an uncoded frequency-hopped (FH), M-ary frequency-shift keyed (MFSK) communication system can be severely degraded by worst case partial band noise or multitone jamming. This paper demonstrates that time diversity, a simplified form of coding, will effectively recover most of this jamming loss, particularly at low error rates.
{"title":"Use of Diversity to Improve FH/MFSK Performance in Worst Case Partial Band Noise and Multitone Jamming","authors":"B. Levitt","doi":"10.1109/MILCOM.1982.4805965","DOIUrl":"https://doi.org/10.1109/MILCOM.1982.4805965","url":null,"abstract":"The performance of an uncoded frequency-hopped (FH), M-ary frequency-shift keyed (MFSK) communication system can be severely degraded by worst case partial band noise or multitone jamming. This paper demonstrates that time diversity, a simplified form of coding, will effectively recover most of this jamming loss, particularly at low error rates.","PeriodicalId":179832,"journal":{"name":"MILCOM 1982 - IEEE Military Communications Conference - Progress in Spread Spectrum Communications","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1982-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123333158","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 : 1982-10-01DOI: 10.1109/MILCOM.1982.4805989
T. Bucher
For signals used as Time Division Multiple Access and Slow Frequency Hopping A-J waveforms, it is desirable to be able to predict the spectrum occupancy of pulses containing a number of angle modulated symbols. It is shown that if the angle modulated signal is random, but stationary in the wide sense, the power or energy spectrum is the convolution of the corresponding spectra of the angle modulated wave and of the amplitude pulse. Spectrum occupancy can be obtained by integrating the resulting spectrum. Using a 9845S desk computer, spectrum occupancy has been estimated for FSK waves having peak to peak deviation ratios of 0.5 (MSK) and 0.7 (approximately optimum for limiter-discriminator). The modulating pulse may be a square wave of duration equal to from one to sixteen FSK symbols, or such a pulse passed through a Butterworth filter (with 2, 4 or 6 poles) or an ideal Gaussian filter. The filtered pulses have a one symbol rise time. It is concluded that square wave modulation should be avoided unless the duration is substantially longer than 16 bits. The simple 2-pole Butterworth filter confines the spectrum about as well as the ideal Gaussian, and much better than the square pulse. Pulsed FSK signals should be provided with a rise (and fall) time of the order of one modulation period. The amplitude variation should be continuous from zero to maximum, and probably the first derivative of the variation should also be continuous.
{"title":"Spectrum Occupancy of Pulsed FSK","authors":"T. Bucher","doi":"10.1109/MILCOM.1982.4805989","DOIUrl":"https://doi.org/10.1109/MILCOM.1982.4805989","url":null,"abstract":"For signals used as Time Division Multiple Access and Slow Frequency Hopping A-J waveforms, it is desirable to be able to predict the spectrum occupancy of pulses containing a number of angle modulated symbols. It is shown that if the angle modulated signal is random, but stationary in the wide sense, the power or energy spectrum is the convolution of the corresponding spectra of the angle modulated wave and of the amplitude pulse. Spectrum occupancy can be obtained by integrating the resulting spectrum. Using a 9845S desk computer, spectrum occupancy has been estimated for FSK waves having peak to peak deviation ratios of 0.5 (MSK) and 0.7 (approximately optimum for limiter-discriminator). The modulating pulse may be a square wave of duration equal to from one to sixteen FSK symbols, or such a pulse passed through a Butterworth filter (with 2, 4 or 6 poles) or an ideal Gaussian filter. The filtered pulses have a one symbol rise time. It is concluded that square wave modulation should be avoided unless the duration is substantially longer than 16 bits. The simple 2-pole Butterworth filter confines the spectrum about as well as the ideal Gaussian, and much better than the square pulse. Pulsed FSK signals should be provided with a rise (and fall) time of the order of one modulation period. The amplitude variation should be continuous from zero to maximum, and probably the first derivative of the variation should also be continuous.","PeriodicalId":179832,"journal":{"name":"MILCOM 1982 - IEEE Military Communications Conference - Progress in Spread Spectrum Communications","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1982-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127710728","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 : 1982-10-01DOI: 10.1109/MILCOM.1982.4806024
M. R. Dresp, D. Leichtman
The effects of ionospheric scintillation on the performance of a UHF (240 MHz) satellite communications link are deduced from experimental data. Scintillation data from the polar cap region and the auroral oval region taken during the 1980-81 period are presented. The performance of the Air Force Satellite Communications (AFSATCOM) digital data satellite link is described for two high latitude sites. The AFSATCOM system uses noncoherent binary frequency shift keying (FSK) modulation at 75 b/s and matched filter detection. Performance is described in terms of bit-error-rate (BER), character-error-rate (CER), and message-error-rate (MER). The recorded bit stream of the experimental data was used as the basis for the evaluation of several scintillation fading mitigation techniques. These techniques, which do not involve coding and interleaving, are shown to improve link performance significantly for the mitigated messages. The penalty paid in reduced channel throughput rate is moderate.
{"title":"Mitigation Techniques against Ionospheric Scintillation on UHF Satellite Links","authors":"M. R. Dresp, D. Leichtman","doi":"10.1109/MILCOM.1982.4806024","DOIUrl":"https://doi.org/10.1109/MILCOM.1982.4806024","url":null,"abstract":"The effects of ionospheric scintillation on the performance of a UHF (240 MHz) satellite communications link are deduced from experimental data. Scintillation data from the polar cap region and the auroral oval region taken during the 1980-81 period are presented. The performance of the Air Force Satellite Communications (AFSATCOM) digital data satellite link is described for two high latitude sites. The AFSATCOM system uses noncoherent binary frequency shift keying (FSK) modulation at 75 b/s and matched filter detection. Performance is described in terms of bit-error-rate (BER), character-error-rate (CER), and message-error-rate (MER). The recorded bit stream of the experimental data was used as the basis for the evaluation of several scintillation fading mitigation techniques. These techniques, which do not involve coding and interleaving, are shown to improve link performance significantly for the mitigated messages. The penalty paid in reduced channel throughput rate is moderate.","PeriodicalId":179832,"journal":{"name":"MILCOM 1982 - IEEE Military Communications Conference - Progress in Spread Spectrum Communications","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1982-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128142020","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 : 1982-10-01DOI: 10.1109/MILCOM.1982.4805931
K. Woo
The time synchronization problem of frequency hopping DPSK signals is considered in this paper. Before DPSK data can be properly demodulated by the receiver several dimensions of time synchronization must first be achieved. These include the acquisition and tracking of the frequency hop time epoch, symbol synchronization of the DPSK data stream, and the frame synchronization which involves the determination of the first DPSK bit within each hop period. Two symbol sync structures for DPSK signals, with and without data aiding, are first discussed. They are optimal in the Gaussian noise channel in the sense that they are both motivated by maximum a posteriori (MAP) estimation theory. Methods for acquiring the frequency hop time and its tracking for this type of signal, as well as the determination of the first DPSK symbol in each hop, are next discussed. The effect of symbol sync error on the probability of DPSK detection error is analyzed. Numerical results showing the bit error as a function of both fixed and random symbol sync error are given.
{"title":"Synchronization of Frequency Hopping DPSK Signals","authors":"K. Woo","doi":"10.1109/MILCOM.1982.4805931","DOIUrl":"https://doi.org/10.1109/MILCOM.1982.4805931","url":null,"abstract":"The time synchronization problem of frequency hopping DPSK signals is considered in this paper. Before DPSK data can be properly demodulated by the receiver several dimensions of time synchronization must first be achieved. These include the acquisition and tracking of the frequency hop time epoch, symbol synchronization of the DPSK data stream, and the frame synchronization which involves the determination of the first DPSK bit within each hop period. Two symbol sync structures for DPSK signals, with and without data aiding, are first discussed. They are optimal in the Gaussian noise channel in the sense that they are both motivated by maximum a posteriori (MAP) estimation theory. Methods for acquiring the frequency hop time and its tracking for this type of signal, as well as the determination of the first DPSK symbol in each hop, are next discussed. The effect of symbol sync error on the probability of DPSK detection error is analyzed. Numerical results showing the bit error as a function of both fixed and random symbol sync error are given.","PeriodicalId":179832,"journal":{"name":"MILCOM 1982 - IEEE Military Communications Conference - Progress in Spread Spectrum Communications","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1982-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129681430","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 : 1982-10-01DOI: 10.1109/MILCOM.1982.4805938
G. O'Clock
Many organizations that are involved in driving military communications components and system technologies to higher levels of performance and integration must be aware of the impacts these technologies will have on manufacturing, technology transfer delays, yield, cost and manpower. Advanced material processing techniques can provide the degree of structural control to produce devices and semiconductor chips with a variety of performance capabilities far exceeding conventional performance levels. However, the yield and cost reductions associated with some of these advanced material processing techniques may not be at the same level as those associated with more conventional processing methods utilized in the fabrication of conventional devices and semiconductor chips. Also, some of the advanced processing techniques may be quite difficult to implement and automate in a manufacturing environment.
{"title":"Impact of Advanced Material Processing Techniques on Spread Spectrum Systems Technology","authors":"G. O'Clock","doi":"10.1109/MILCOM.1982.4805938","DOIUrl":"https://doi.org/10.1109/MILCOM.1982.4805938","url":null,"abstract":"Many organizations that are involved in driving military communications components and system technologies to higher levels of performance and integration must be aware of the impacts these technologies will have on manufacturing, technology transfer delays, yield, cost and manpower. Advanced material processing techniques can provide the degree of structural control to produce devices and semiconductor chips with a variety of performance capabilities far exceeding conventional performance levels. However, the yield and cost reductions associated with some of these advanced material processing techniques may not be at the same level as those associated with more conventional processing methods utilized in the fabrication of conventional devices and semiconductor chips. Also, some of the advanced processing techniques may be quite difficult to implement and automate in a manufacturing environment.","PeriodicalId":179832,"journal":{"name":"MILCOM 1982 - IEEE Military Communications Conference - Progress in Spread Spectrum Communications","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1982-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121103619","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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