臺灣博碩士論文加值系統

本論文是針對單頻和多頻直序展頻系統於高斯白雜訊通道 (AWGN) 或多路徑衰落通道 (multipath fading channels) 下提出四個議題和解決方案。
第一部份裡，我們針對單頻直序展頻 (DS-SS) 系統於高斯白雜訊通道下提出一個新的架構稱為碼-都卜勒 (code-Doppler) 補償之擬亂碼追蹤器 (code tracking)，因為碼-都卜勒補償的關係使得主動相關器可以加比較長的長度而讓系統性能變的更好。在越大的碼-都卜勒效應下，此架構越能改善其系統性能。
在第二部份裡是針對單頻直序展頻系統在高斯白雜訊通道下提出新的追蹤器分析方法，此追蹤器分析方法並將類比/數位的轉換效果(A/D quantization)考慮進來。在都卜勒效應下我們針對非同調 (noncoherent) 二階數位式延遲鎖定迴路 (digital delay lock loops) 作性能分析。我們提出一個新的分析方法-再生馬可夫鍊模型 (regenerative Markov chain modeling) ，然後再把類比/數位的轉換效果考慮進來。數值結果顯示類比/數位的轉換效果對於迴路的暫時響應 (transient responses)，鎖住能力 (lock-in range)，失鎖的平均時間 (mean time to lose lock) 及平均平方誤差 (mean square error) 都有深遠的影響。
第三部份裡，我們探討了多頻 (multicarrier) 直序碼多工器 (DS-CDMA) 在多路徑衰落通道下，其碼捕捉 (code acquisition) 系統的性能分析。在多路徑衰落通道下，由於通道的相關性使得碼捕捉系統的性能分析變的很困難。在此本文針對多頻直序碼多工器之捕捉系統在使用串取搜尋 (serial search) 多重推積檢測器下 (multiple dwell)，提出一個精確分析平均捕捉時間的方法。
最後在考慮自動大小控制 (AGC)，多路徑衰落及其他使用者的干擾下，本文探討多頻直序碼多工器傳統非同調碼追蹤系統的性能分析。同時我們使用差值檢測器 (differential-detected) 去建構一個新的非同調追蹤迴路器。此新的追蹤器比起傳統的追蹤器有更好的系統性能。

Four issues and solutions are investigated in the thesis with regard to the pseudo-noise (PN) code synchronization for single- and multi-carrier direct sequence spread spectrum (DS-SS) systems operating on additive white Gaussian noise (AWGN) and/or multipath fading channels.
In the first part, code tracking with code-Doppler compensation for single carrier DS-SS systems on AWGN channels is proposed. Code Doppler compensation
is introduced to the traditional noncoherent digital delay lock loop (DLL)
in addition to carrier Doppler compensation. Thanks to the code Doppler compensation, the simple-to-implement active correlation with a large correlation length can be employed to improve the loop performance. The code Doppler compensation significantly improve the loop performance with the presence of a large code Doppler.
In the second part, new tracking loop analysis with A/D quantization for single carrier DS-SS systems on AWGN channels is considered. In particular, the performance of non-coherent second-order all digital delay lock loops with the presence of Doppler shift is analyzed. A new method based on a regenerative Markov chain modeling of the tracking process is proposed with the loop A/D quantization being taken into account that has been neglected in previous analyses. Numerical results show that A/D
quantization has a significant impact on the loop performance, including loop transient responses, lock-in range, mean time to lose lock (MTLL) and mean square error (MSE). In addition, by using saddle point integration
for the evaluation of the transition probabilities of the Markov chain, MTLL and MSE is evaluated more accurately than previous methods.
In the third part, the code acquisition for multicarrier direct sequence code division multiple access (DS-CDMA) systems on multipath fading channels is investigated. For multipath fading channels, the exact analysis of code acquisition becomes difficult because of the channel memory incurred by multipath fading. In this part, a new analysis is given to accurately evaluate the mean acquisition time performance of the serial search multiple dwell code acquisition for the multicarrier DS-CDMA systems. Our analysis can take the fading correlations into account, the effects of system parameters on the acquisition performance such as carrier and user numbers, fading correlations, dwell''s number, times and thresholds can be easily evaluated, and, therefore, facilitating the design of the acquisition subsystem.
Finally, code tacking for multicarrier DS-CDMA systems on multipath fading channels is investigated. In this part, the tracking error performance of the traditional noncoherent DDLL with diversity reception is analyzed for the multicarrier DS-CDMA systems, under the effects of automatic gain control (AGC), multipath fading, and multiple access interference. AGC is used to eliminate the inherent stability problem of a DDLL. And, a new decision-directed noncoherent tracking loop based on a differentially-detected phase detector is proposed and analyzed. The new tracking loop outperforms the traditional DDLL.

Cover
Abstract
Contents
1 Introduction
1.1 Issues and Solutions
1.2 Organization of Thesis
2 A New Digital Code Tracking Loop with Code-Doppler Compensation
2.1 System Overview
2.2 DLL with Code Doppler Compensation
2.3 Numerical Results
2.4 Summary
3 Performance Analysis of Digital Second Order Delay Lock Loops for Direct Sequence Spread Spectrum Systems with Doppler Shift and A/D Quantization
3.1 Non-coherent Delay Lock Loop
3.2 Performance Analysis
3.3 Numerical Results
3.4 Summary
4 Performance of Multiple-Dwell Code Acquisition with Diversity for Multicarrier DS-CDMA Systems on Multipath Fading Channels
4.1 system Overview
4.2 Performance Analysis
4.3 Numerical Results
4.4 Summary
5 Performance of Digital Code Tracking Loops with Diversity for Multicarrier DS-CDMA Systems on Multipath Fading Channels
5.1 System Model
5.2 Performance Analysis
5.3 Numerical Results
5.4 Summary
6 Conclusions
6.1 Summary of Thesis
Bibliography

M.K. Simon, J.K. Omura, R. A. Scholtz, and B.K. Levitt,
Spread Spectrum Communications} Vol. III. MD: Computer Science
Press, 1985.
R.L. Peterson, R.E. Ziemer and D.E. Borth, \bf Introduction to Spread Spectrum Communications},
NJ: Prentice-Hall, 1995.
R.E. Ziemer and R.L. Perterson, Digital Communications and Spread Spectrum Systems, Prentice-Hall, Englewood cliffs, N.J., New York, 1985.
J.K. Holmes, \bf Coherent Spread Spectrum Systems}, NY:
Wiley,1982.
C.R. Cahn, D.K. Limber, CL. Marsh, F.J. Huntowski,
and G.D. Lauren, ''Software implementation of a PN spread spectrum
receiver to accommodate dynamics," \it IEEE Trans. Commun.}, Vol.~ COM-25,
pp.~832-839, August 1977.
Cheng, U., Hurd, W.J. and Statman, J.I. '' Spread spectrum
code acquisition schemes in the presence of Doppler shift and data modulation,"
IEEE Trans. Commun.,} Vol. COM-38, pp.~241-250, February 1990.
M. Katayama, A. Ogawa, and. N. Morinaga, ''Carrier synchronization
under Doppler shift of the nongeostationary satellite
communication systems," \it in Proc.
IEEE ICCS/ISITA''92}, pp.~466-470, 1992.
\she2} W-H. Sheen, M-J. Chang and C-S. Wu, ''
A digital code tracking loop with code-Doppler compensation
for direct sequence spread spectrum systems,"
submitted for publication, March 2000.
om1} C.A. Pomalaza-Raez and C.D. McGillem, ''Digital phase-locked
loop behavior with clock and sampler quantization," \it IEEE Trans. Commun.},
Vol.~ COM-33, pp.~753-759, August 1985.
\ros1} S.M. Ross, \bf Stochastic Processes,}
2rd Edition, NY: John Wiley \& Sons, 1996.
\axe1} O. Axelsson, \bf Iterative Solution Methods,chapters 5,6} Cambridge:
Cambridge University Pres, 1994.
\hel1} C.W. Helstrom, \bf Elements of Signal Detection and Estimation,"}
NJ: Prentice Hall, 1995.
\omu1} J. Omura and T. Kailath, \bf Some Useful Probability Distributions,}
Technical Report No. 7050-6, Stanford University, September 1965.
\gau1} R.D. Gaudenzi, M. Luise, and R. Viola, ''A digital chip timing
recovery loop for band-limited direct-sequence spread spectrum signals,"
\it IEEE Trans. Commun.}, Vol.~ COM-41, pp.~1760-1769, November, 1993.
\kal1} K. Kallaman and G. Davis, ''Jitter performance of a baseband sampled
code tracking loop," \it IEEE Trans. Commun.}, Vol.~ COM-42, pp.~2919-2925, November
1994.
\yen1} N-Y. Yen, S-L. Su and S-C. Hsieh, ''Performance analysis of digital delay
lock loops in the presence of Doppler shift," \it IEEE Trans. Commun.}, Vol.~
COM-44,
pp.~668-673, June 1996.
\bie1} J.K. Holmes and L. Biederman, "Delay Lock Loop Mean Time to Lose Lock," \em IEEE Trans. Com.}, Vol. COM-26, pp. 1549-1557, Nov. 1978.
\gau2} R. De Gaudenzi and M. Luise, "Decision-Directed Coherent Delay-Lock Tracking Loop for DS-spread Spectrum Signals," \em IEEE Trans. Com.}, Vol.39, pp. 758-765, May 1991.
\Mey2} H.Meyr,"Delay-Lock Tracking of Stochastic Signals," \em IEEE Trans. Com.}, Vol. COM-24, pp. 331-339, Mar. 1976.
\sim2} M.K Simon, "Noncohereht Pseudonoise Code Tracking Performance of Spread Spectrum Receivers," \em IEEE Trans. Com.}, Vol. Com-25, pp. 327-345, Mar. 1997.
\Kar1} R. Karmy, B.Z. Bobrovsky, and Z. Schuss, " Loss of Lock Induced by Doppler or Code Rate Mismatch in Code Tracking Loops," MILCOM ''87, Washington, pp. 294-298, Oct.1987.
ol1} A. Polydoros and C.L Weber, "Analysis and Optimization of Correlative Code-Tracking Loops in Spread Spectrum Systems, \em IEEE Trans. Com.}, Vol. COM-33, pp.30-34, 1985.
\zhu1} W. Zhuang and J. Tranquilla, ''Modeling and analysis for the
GPS pseudo-range observable," \it IEEE Trans. Aerospace and Electronic System,}
Vol. ~AES-31, pp.~739-751, April 1995.
\yee1} N. Yee, J.P. Linnartz, and G. Fettweis, ''Multi-carrier CDMA in indoor wireless radio," \it IEEE PIMRC''93}, pp.~D3.2.1-5, December 1993.
\cho1} A. Chouly, A. Brajal and S. Jourdan, ''Orthogonal multicarrier techniques applied to direct sequence spread spectrum CDMA systems," \it IEEE GLOBECOM''93}, pp.~1723-1728, November, 1993.
\faz1} K. Fazel, ''Performance of CDMA/OFDM for mobile communication systems," \it IEEE ICUPC''93}, pp.~ 975-979, 1993.
\mue1} T. Mueller, K. Brueninghaus, and H. Rohling, ''Performance of coherent OFDM-CDMA for broad-band mobile communications,"\it Wireless Personal Communications}, Vol.~2, pp.~295-305, 1995/1996.
\das1} V.M. DaSilva and E.S. Sousa, ''Multicarrier orthogonal CDMA signals for quasi-synchronous communication systems," \it IEEE Journal on Selected Areas in Communications,} Vol. JSAC-12, pp.~842-852, June 1994.
\van1} L. Vandendorpe, ''Multitone spread spectrum multiple-access communications system in a multipath Rician fading channel," \it IEEE Trans. Vehicular Technology}, Vol. VT-44, pp.~327-337, May 1995.
\kno1} S. Kondo and L.B. Milstein, ''Performance of
multi-carrier DS CDMA systems," \it IEEE Trans. Commun.}, Vol.~ COM-44, pp.~238-246, February 1996.
\sou1} E.A. Sourour and M. Nakagawa, ''Performance of
orthogonal multicarrier CDMA in a multipath fading channel,"
\it IEEE Trans. Commun.}, Vol.~ COM-44, pp.~356-367, March 1996.
\faz2} K. Fazel and G. P. Fettweis (Editors), \bf Multi-Carrier Spread-Spectrum,} Boston: KAP, 1997.
ra1} R. Prasad and S. Hara, ''An overview of multi-carrier CDMA," \it IEEE ISSSTA''96,} pp.~107-114, Sept. 1996.
\sou2} E. Sourour and S.C. Gupta, ''Direct-sequence spread-spectrum parallel acquisition in a fading mobile channel,"\em IEEE Trans.
Commun.,} Vol. COM-38, pp.~992-998, July 1990.
\sou3} E. Sourour and S.C. Gupta, ''Direct-sequence spread-spectrum parallel acquisition in nonselective and frequency-selective Rician channels,"
\em IEEE Journal on Selected Areas in Commun.}, Vol. SAC-10, pp.~535-544, April 1992.
\ibr1} B.B. Ibrahim and H. Aghvami, ''Direct-sequence spread spectrum matched filter acquisition in frequency-selective Rayleigh fading channels," \em IEEE Journalon Selected Area in Commun.,} Vol.~JSAC-12, pp.~885-890, June, 1994.
\chu1} C-D. Chung, ''Differentially coherent detection technique for direct-sequence code acquisition in a Rayleigh fading mobile channel,"
\it IEEE Trans.
Commun.,} Vol. COM-43, pp.~1116-1126, Feb./March/April, 1995.
\ric1} R.R. Rick and L.B. Milstein, ''Parallel acquisition in mobile DS-CDMA systems, " \em IEEE Trans. on Commun.,} Vol. COM-45, pp.~1466-1476, November 1997.
\ric2} R.R. Rick and L.B. Milstein, ''Optimum decision strategies for acquisition of spread-spectrum signals in frequency-selective fading channels, " \em IEEE Trans. on Commun.,} Vol. COM-46, pp.~686-694, May 1998.
\sch1} P. Sch \"a}fer and M. Nakagawa, ''Direct-sequence multi-carrier CDMA parallel acquisition in a multipath fading channel," \it IEEE }, pp.~1503-1507,
\dic1} D.M. DiCarlo and C.L. Weber, ''Multiple dwell serial search: performance and application to direct sequence code acquisition," \em IEEE Trans. on Commun.,} Vol. COM-31, pp.~650-659, May 1983.
ol2} A. Polydoros and C.L. Weber, ''A unified approach to serial search spread-spectrum code acquisition- part I: general theory," \em IEEE Trans. on Commun.,} Vol. COM-32, pp.~542-549, May 1984.
ol3} A. Polydros, "On the syschronization aspects of direct-sequence spread spectrum systems", Ph.D Disseration, Department of Electrical Eng., Universiy of Southern California, August 1982.
\vit1} A. J. Viterbi, \bf CDMA- Principles of spread spectrum Communication}, NY:Addison-Wesley, 1995.
\hel1} C.W. Helstrom, \bf Elements of Signal Detection \& Estimation},
NJ: Prentice-Hall, 1995.
\roy1} T. Royen, ''On some central and non-central multivariate
chi-square distributions'''', \em Statistica Sinica}, Vol.~5, No.~1, pp.~373-397,
1995.
\giri} N.C. Giri, \bf Multivariate statistical analysis}, New York:
M. Dekker, 1996.
ro1} J.G. Proakis, \bf Digital Communications}, New York:
McGraw-Hill, 1995.
\jak1} W.C. Jakes, Jr., \bf Microwave Mobile Communications},
NY: John Wiley \& Sons, 1974.
\bernt} J. Berntsen, T.O. Espelid and A. Genz, ''An adaptive
algorithm for the approximate calculation of multiple integrals'''', \em ACM
Trans. Math. Soft.} Vol.~17, No.~4, pp.~437-451, Dec. 1991.
\krom} A.R. Krommer and C.W. Ueberhuber, \bf Numerical
Integration}, Berlin; New York: Springer-Verlag, 1994.
\she4} W-H. Sheen ''Adaptive equalization for wireless TDMA personal communication systems," Tech. Rep. NSC-84-2221-E-194-004, National Chung Cheng University, 1994.
\sto1} R. Storn and K. Price, ''Differential evolution- a simple and efficient adaptive scheme for global optimization over continuous spaces," Technical Report TR-95-012, ICSI, UC-Berkeley, March 1995.
\sto2} R. Storn and K. Price, ''Minimizing the real functions of the ICEC''96 contest by differential evolution," \it 1996 IEEE ICEC,} Japan, 1996.
\genz} A. Genz, ''Statistics applications of subregion adaptive
multiple numerical integration'''', pp.~267-280, Numerical Integration,
Edited by T. O. Espelid and A. Genz, Dordrecht; Boston:
Kluwer Academic, 1992.
\wan1} H.C. Wang and W.H Sheen, "Variable Dwell-Time code Acquisition for Direct Sequence Spread Spectrum Systems on Time-Variant Rayleigh Fading Channels," \em IEEE Trans. Commun.}, Vol. COM-48, pp. 1037-1046, June 2000.
\ett1} W-H. Sheen, M-J. Chang, H-C. Wang and C-S. Wu, ''Pseudo-noise code synchronization of multicarrier
DS-CDMA systems on multipath fading channels part I: A new analysis on the
code acquisition subsystem,", \em ETT Vol.10.No.4, July/August 1999}.
\bra1} W.R. Braum, ''PN acquisition and tracking performance in DS/CDMA systems with symbol-length spreading sequences," \it IEEE Trans. Commun.}, Vol.~ COM-45, pp.~1595-1601, December 1997.
\wel1} A.L. Welti and B.Z. Bobrovsky, ''On optimal AGC structure for direct sequence spread spectrum PN-code tracking," \it IEEE Trans. Commun.}, Vol.~ COM-42, pp.~680-687, Feb./March/April 1994.
\she5} W-H. Sheen and St\"u}ber, G.L., ''A New Tracking
Loop for Spread-Spectrum Systems on Frequency-Selective Fading Channels,"
\em IEEE Transactions on Communications}, Vol.~COM-43, pp.~3063-3072,
December 1995.
\she6} W-H. Sheen and Chien-Hsiang Tai, ''A Noncoherent Tracking Loop with Diversity and Multipath Interference
Cancellation for Direct Sequence Spread Spectrum Systems," \em IEEE Transactions on Communications.}, Vol. COM-46, pp. 1516-1524, Nov 1998.
ic2} R.L. Pickholtz, L.B. Milstein, and D.L. Schilling, "Spread
spectrum for mobile communications",\em IEEE Trans. Veh. Technol.}, VT-40,
pp.~313-322.
\she7} W-H. Sheen, M-J. Chang and C-S. Wu, "Pseudo-Noise Code Synchronization of Multicarrier DS-CDMA Systems on Multipath Fading channels-part 2: Digital Code Tracking with Diversity," ETT vol.10, No.4, July/August 1999.
\sag1} G.F. Sage, "Serial synchronization of pseudonoise systems,"
\em IEEE Trans. Commun.,} Vol.~COM-12, pp.~123,127, Dec. 1964.
\eia2} EIA/TIA-IS95, Mobile station-base station compatibility
standard for dual-mode wide-band spread spectrum cellular system, July,
1993.
\war1} R. B. Ward, "Acquisition of pseudonoise signals by sequential
estimation", \em IEEE Trans. Commun.} COM-13, pp.~475-483, December 1965.
\war2} R. B. Ward and K. P. Yiu, "Acquisition of preseudonoise
signals by recursion aid sequential estimation," \em IEEE Trans. Com.},COM-25, pp.~784-794,
August 1977.
\gil1} K.S. Gilhousen, I.M. Jacobs, R. Padovani, abd L.A. Weaver, "Increased capacity using CDMA for mobile satellite communication," \em IEEE J.Select. Areas Com.,} vol.8. no.4, pp. 503-514, May 1990.
\lee1} W. C. Y. Lee, "\bf Mobile Communications Engineering}", New
York: McGraw Hill, 1982.
\kon1} J. Kondo, \bf Integral Equation}, Tokyo: Oxford University Press, 1991.