In this paper, planar power dividers/combiners for millimeter waves K-band or bands which can be printed on the substrates of hybrid or monolithic IC by surface mounting are designed and studied. Power dividers/combiners, and the conductor loss of microstrip lines in particualr the existing Wilkinson power dividers/combiners is modified ad amployes by ist equivalent circuit. Microwave CAD program SUPEROMPACT is employed for the Wilkinson power combiner which is modified and analyzed to reduce the high frequency coupling between the branches of the combiner, and the method to diminish the sensitivity of the input reflection of -way power dividers/combiners is studied employing the commerical microwave CAD program package SUPERCOMPACT.

In tnis paper, the CRC-CCITT code and primitive polynomial CRC code are selected for analysing error detecting performance. However, general formulas for obtaining the weight distribution of these two CRC codes are not so far dericed. So, a new method for calculating the weight distribution of the shortened cyclic Hamming code is presented and an undetected error probability of these two codes is obtained when used in cell of ATM for broadband ISDN user-network interface. Consequently, we show that CRC code too much does affect its error detection performance. All the computer simulation is performed by IBM PC/AT.

As the volume of communication data and information exchange, the protection of data which we want to keep secret from invalid users would be a main topic nowadays. This paper describes the use of an arbitrary bit-sequence generating algorithm as the cryptographic key for a stream cipher. Emphasis is places on methods for combining stream generators into more complex ones, with and without randomization.

In this paper, Fingerprint matching method which is able to confirm one's identity using microcomputer is discussed. In matching method, fingerprint image is thinned and we extracted feature point data which is composed of position and direction of end-point and branch-point. Identification is conducted by decision of disagreement between reference finger print and input fingerprint us ing this extracted data. After averaging and binariztion process, thining method is conducted. Restoration process is carried out to seek precise feature pointdatd. We compensate position difference of reference fingerprint and input fingerprint, which is divied end-point and branch-point, and translated and rotated its position. Using this compensdate difference of position, we decide whether fingerp-print identity is true or not.

According to the conventional network evolving towards ISDN, various connection types may be existed in the networks and subscriber-network interfaces. For this reason it is necessary to study the signalling conversion algorithms and the implementation models. In this paper, after surveying the signalling conversion method between the ISDN subscriber and the conventional network, the signaling conversion algorithms are proposed. Based on this algorithms the matching system is designed and developed. Also the validity of this system and the utility of designed software and hardware functions are verified through experiments.

In this paper, we proposed an economical coding method to be applied for Hangeul character, the Korean letter, by utilizing three state transition graph. With this method, only about 3.5 biys are required in expressing a Hangeul character, which is more than 1 bit shorter than conventional codes so far introduced in order to realze extensive code compression. Hence this method will improve the rapidity and exanctitude and economy in processing Hangeul letter.

In this paper the theory of digital filters which can directly process the ADM encoded signal, and their structures are studied. In order to investigate the frequency characteristics of DM filters with the strucutures presented in this paper, a sampled speech signal is used for the input data. The result of computer simulation shows that the presented DM filter structures can be used effectively for the direct process of ADM encoded signals, ven though they do not posses sufficiently sharp cutoff characteristics.

In this paper, a new algorithm for feature extraction and classification of recognizing Hanguel patterns is proposed. Inputed patterns classify into six basic formal patterns and divided into subregion of Hanguel phoneme and extract the crook feature from position information of the each subregion. Hanguel patterns are defined and are made of the indexed-sequence file using these crook features points. Hanguel patterns are recognized by retrievignt ehses two files such as feature indexed-sequence file and standard dictionary file. Thi paper show that the algorithm is very simple and easily construct the software system. Experimental result presents the output of feature extraction and grouping of input patterns. Proposed algorithm extract the crooked feature using distance transformation method within the rectangle of enclosure the characters. That uses the informationof relative position feature. It represents the 97% of recognition ratio.

In order to design the automatic processing system of image document, the pattern segmentation of image document and classification methods are presented. The contour extraction using first order differential operator of Gauassian distribution fucntions, the image segmentation using the chain code, and the pattern classication using the second order moments and two=dimensional Rf distance(in transform domain) are implemented. The resuts applied in specially documantated image shows to classify the characters, fingerprints, seals etc well. And the utility of the used algorithms is verified.

The interconnection network is an integral part of parallel processing system. The multistage interconnection networks(MINs) have been the objects of intense research in recent years. In this paper, simulation techniques for circuit switchign MIN are extended to allow the performance evaluation of partitioned ADM/IADM network. Based on simulation data, the relationship between the netwrok performance, the partitioning scheme employed, and the conflict resolution strategies used within the network is enumerated. It is shown that IADM network coupled with the use of the hold strategy produces the best network operation in terms of RST (Request Service Time).

In this paper, The new algorithm of spectrum moment for format frequency estimation is proposed. The second oder and the third order spectrum moment, which reflect variance and skewness of a spectrum pattern, respectively, is utilized to adjust the frequency region for estimation precision of format frequency. As the results. the F1-F2 diagram reported 8 Korean vowels for man and woman and that we found articulation method of vowel and vowel, vowel and consonant.

This paper describes a method of Korean speech synhes is using format VOCODER. The parameters of speech synthes is are a follows, 1) format F1, F2, and F3 by spectrum moment method and F4, F5 using the length of vocal tract. 2) pitch frequencies obtained by optimu, Comb method using AMDF. 3) short time average energy and short time mean amplitude. 4) The decision method of bandwidth reportd by Fant. 5) voicde/unvoiced discrimination using zerocrossing. 6) excitation wave reported by Rosenberg. 7) gaussian white noise. Synthesis results are in fairly good agreement with original speech.

In this paper, 16-QAM and 49-QPR systems utilized the raised cosine filter instead of LPF with the rectangular frequency characteristics as limiting channel bandwidth are implemented to measure their performances and effects of ISI. With the use of the raised cosine filter, and increase in SNR immunity can be obtained for specified spectrally efficient applications. Examination of the measured results reveals that the bandwidthe efficiency of 49-QPR implement is improved by about 8% and 15% higher than those of 16-QAM implement with the raised cosine characteristics having roll-off factor, a=0.5 and a=1, respectively. Also, equations for eye diagrams and error probability of 49-QPR system with AWGN and ISI are derived to analyze its performance and compared with the case of 16-QAM system.

A spread spectrum(ss) communication system has a lot of advantage, such as realzation of asynchronous code division multiplexing(CDM), robutness to narrow-band interference, impulse noise, privacy function, and so on. We have considered utilization of these advantage to develop a local area network(LAN) using such a transmission channel as power-line. In a power-line, however, restricted bandwidth under the law makes it difficult to carry out CDM, and in a radio channel the sysstem has a near-far problem. These problems originate in co-channel interference, which is due to cross-correlation among pseudo-noise sequences of every channel in CDM. In this paper, we propose a new scheme of easily cancelling co-channel interference and investigate its performance by constructing a LAN using SS technique.