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Full-Text Articles in Engineering

Identification Of The First Limiting Amino Acid In Cooked Polished White Rice Fed To Weanling Holtzman Rats, Mellova Masrizal, J. B. Lamb Dec 2003

Identification Of The First Limiting Amino Acid In Cooked Polished White Rice Fed To Weanling Holtzman Rats, Mellova Masrizal, J. B. Lamb

Makara Journal of Technology

Forty-eight male weanling rats (91 g) were utilized to study the nutritional adequacy of cooked polished white rice. Rats were individually housed, and allowed ad libitum access to one of six treatment diets. Treatment diets were 1) polished white rice plus 10% casein and 0.18% methionine, CAS, 2) polished white rice, WHR, 3) polished white rice plus 0.45% lysine, LYS, 4) polished white rice plus0.40% methionine, MET, 5) polished white rice plus 0.30% threonine, THR, 6) polished white rice plus 0.45% lysine, 0.40% methionine, and 0.40% threonine, COM. Rice was cooked prior diet formulation using a 3 to 1 ratio …


Adoption Of Variable Rate Technology, Isti Surjandari, Marvin T. Batte Dec 2003

Adoption Of Variable Rate Technology, Isti Surjandari, Marvin T. Batte

Makara Journal of Technology

Site Specific Management (SSM), which also variously referred to as Variable Rate Technology (VRT), is an emerging technology that enables producers to make more precise input application decisions based on soil and field characteristics. This study analyzes factors influencing the adoption of VRT for fertilizer application for cash grain production in Ohio. Results show that producer and field characteristics might influence the adoption decision on various SSM components differently. It also provides insight as to the sequence of adoption of SSM component technologies and how this sequence might differ for producers of differing characteristics.


An Economic Analysis Of Variable Rate Technology, Isti Surjandari, Marvin T. Batte, Mario J. Miranda Dec 2003

An Economic Analysis Of Variable Rate Technology, Isti Surjandari, Marvin T. Batte, Mario J. Miranda

Makara Journal of Technology

Variable Rate Technology (VRT) offers an opportunity to improve production efficiency by allowing input applications to fluctuate in response to spatial variations in soil characteristics and nutrient levels. Society may also benefit from reduced negative externalities, such as surface and groundwater contamination, from input applications. Using a dynamic spatial model, this study examines how the interaction among variability, spatial autocorrelation, and mean level of soil fertility affects optimal sampling density and the economic gains from VRT. VRT was found to be profitable under selected conditions, and the optimal grid size will vary with these conditions. In the case where variability …


Alum And Pacl Coagulation, Winarni Winarni Dec 2003

Alum And Pacl Coagulation, Winarni Winarni

Makara Journal of Technology

Alum and PACl Coagulation. Coagulation occurs by interaction of aluminum hydrolysis products with the contaminant such as colloidal particles. It is necessary to consider the different aluminum species that may present during specific conditions, since the mechanism of turbidity removal is dependent upon them. PACl consists of preformed aluminum hydrolysis products, which are stable below pH 6 and less sensitive than in situ hydrolysis product, alum. The benefits of PACl relative to alum have been investigated as a function of pH and Al dosages. Specific conditions and aluminum species that exist during the certain mechanisms of coagulation are discussed. Results …


Study On Electrochromic Effect Of Polyaniline Film, Lienda Handojo, Junus Simangunsong Dec 2003

Study On Electrochromic Effect Of Polyaniline Film, Lienda Handojo, Junus Simangunsong

Makara Journal of Technology

Study on Electrochromic Effect of Polyaniline Film. The light transmission factor of an electrochromic film changes reversibly with the application of an electrical voltage. Thereby the transparent film becomes reversibly opaque so that it may be used to control light transmission. In this paper the results of a study on polyaniline film as an electrochromic active material is reported. Polyaniline looks yellow transparent in the reduced state and turns to green-blue at its oxidized state. The electrochromic device considered in this paper was fabricated in planar configuration of ITO glass − polyaniline film − electrolyte − ITO glass which involved …


Application Of Tabu Search Algorithm In Job Shop Scheduling, Betrianis Betrianis, Putu Teguh Aryawan Dec 2003

Application Of Tabu Search Algorithm In Job Shop Scheduling, Betrianis Betrianis, Putu Teguh Aryawan

Makara Journal of Technology

Application of Tabu Search Algorithm in Job Shop Scheduling. Tabu Search is one of local search methods which is used to solve the combinatorial optimization problem. This method aimed is to make the searching process of the best solution in a complex combinatorial optimization problem(np hard), ex : job shop scheduling problem, became more effective, in a less computational time but with no guarantee to optimum solution.In this paper, tabu search is used to solve the job shop scheduling problem consists of 3 (three) cases, which is ordering package of September, October and November with objective of minimizing makespan (Cmax). …


Role Of K3-Xhxpw12o40 As A Catalyst In Selective Catalysis Of Methylamine Synthesis From Ammonia And Methanol, Mohammad Nasikin Dec 2003

Role Of K3-Xhxpw12o40 As A Catalyst In Selective Catalysis Of Methylamine Synthesis From Ammonia And Methanol, Mohammad Nasikin

Makara Journal of Technology

Role of K3-xHxPW12O40 as a Catalyst in Selective Catalysis of Methylamine Synthesis from Ammonia and Methanol. Synthesize of methylamine from methanol and ammonia was studied in this research work using a partially potassium heteropoly salt (K3-xHxPW12O40 abbreviated as KPW) as a catalyst. KPW was prepared from heteropoly salt and potassium carbonate by using ion exchange method. The reaction was conducted at 600 ~ 800K and at the atmospheric pressure. Reactor used was a continue flow reactor with W/F=0,1~0,9g-kat.mnt./cc.Concentration of reactants and products were analyzed by gas chromathography while catalyst structure was observed by XRD (X-ray diffraction). Isothermal adsorption method was …


The Selection Of Materials For Roller Chains From The Perspective Of Manufacturing Process, Rahmat Saptono Dec 2003

The Selection Of Materials For Roller Chains From The Perspective Of Manufacturing Process, Rahmat Saptono

Makara Journal of Technology

The selection of materials for an engineering component is not only requested by its design function and shape, but also the sequence through which it is manufactured. The manufacturing operation of roller chains involves drawing and trimming processes aimed at producing semi-finished chain drives component with a well-standardized dimension. In addition to final combination of properties required by design constraints, the ability of materials to be formed into a desired shape and geometry without failure is also critical. The objective of materials selection should therefore involve additional attributes that are not typically accommodated by the standard procedure of materials selection. …


The Performance Analysis Of A Unicast Network When Two Protocols, Sctp (Stream Control Transmission Protocol) And Tcp (Transmission Control Protocol) Coexist In The Network, Bagio Budiardjo, Michael Thiotrisno Aug 2003

The Performance Analysis Of A Unicast Network When Two Protocols, Sctp (Stream Control Transmission Protocol) And Tcp (Transmission Control Protocol) Coexist In The Network, Bagio Budiardjo, Michael Thiotrisno

Makara Journal of Technology

This paper elaborates the performance analysis of a unicast network when two protocols, SCTP (Stream Control Transmission Protocol) and TCP (Transmission Control Protocol) coexist in the network. These two protocols are tested using File Transfer Protocol (FTP) and Constant Bit Rate (CBR) based traffic. From the simulations, it could be concluded that SCTP could achieve better throughput compared to TCP in both FTP and CBR based traffic, with sufficiently high fairness index of both intrafairness and interfairness. The increase of simulation time yields to the increase and relatively stable network performance. The increase of the number of sessions of small …


Capacity Of High-Speed Powerline Communication In Vehicles, Deny Hamdani, Ery Safrianti Aug 2003

Capacity Of High-Speed Powerline Communication In Vehicles, Deny Hamdani, Ery Safrianti

Makara Journal of Technology

Powerline Communication (PLC) Systems intents to use the mains network in vehicles for high-speed data transmission. Carrier frequencies in the range of MHz are required to establish data rates of some megabits per second. In this paper, typical reference channels extracted from channel measurements are presented and computation results of their capacities according to Shannon’s theorem are presented. Furthermore, the effect of limitations of frequency range and power spectral density of transmitted signal on achievable capacity is investigated. This paper outlines an assessment for theoretical channel capacity and achievable data rates of vehicular PLC transmission schemes. Finally, EMC (Electromagnetics Compatibility) …


The Study On Fluorescence Characteristics Of Chlorella Spp: Ph Influence On Culture, Retno Wigajatri P., Andrianto Handojo, Hendrik Kurniawan, N. B. Prihantini Aug 2003

The Study On Fluorescence Characteristics Of Chlorella Spp: Ph Influence On Culture, Retno Wigajatri P., Andrianto Handojo, Hendrik Kurniawan, N. B. Prihantini

Makara Journal of Technology

The Study on Fluorescence Characteristics of Chlorella spp: pH Influence on Culture. Experiments for measuring the fluorescence characteristics of Chlorella spp. by using high stability and high repetition rate nitrogen laser of energy 5 mJ with pulse duration of 5 ns have been carried out. The results show that for a cell concentration range from 2,625 cells/ml up to 2,769,000 cells/ml, the fluorescence intensities at pada λ = 687 nm have a linear relationship with the cell concentration. It has been also found that for a 7 days old chlorella culture, the pH variation at the starting culture influenced the …


Diffuser Optimation At Exhaust System With Catalytic Converter For 110 Cc Mopet With Fluid Flow Cfd Simulation, Tresna P. Soemardi, Ahmad Indra Siswantara, Erwin Erwin Aug 2003

Diffuser Optimation At Exhaust System With Catalytic Converter For 110 Cc Mopet With Fluid Flow Cfd Simulation, Tresna P. Soemardi, Ahmad Indra Siswantara, Erwin Erwin

Makara Journal of Technology

Diffuser Optimation at Exhaust System with Catalytic Converter for 110 cc Mopet with Fluid Flow CFD Simulation. CFD simulation used to get behavior of exhaust gas through catalyst, this result will be used to optimize geometry form to perform uniform stream distribution to catalyst, and CFD Simulation will used to analyze backpressure that happened at the model.


Mapping Of Ecosystems In Mount Bromo Using Remote Sensing Technology, Bangun Muljo Sukojo Aug 2003

Mapping Of Ecosystems In Mount Bromo Using Remote Sensing Technology, Bangun Muljo Sukojo

Makara Journal of Technology

Mapping of Ecosystems in Mount Bromo Using Remote Sensing Technology. Covered land analyses of Landsat image have been done to get ecosystem types and map in Mount Bromo region using remote sensing technology. There are nine types of ecosystems in Mount Bromo region, i.e. primary forest, secondary forest, lake, crater, sands, uncovered land, underbrush, dry-field and residence. Distribution of rock analysis has also been done by comparing the manual image interpretation with geological map. The results were coorelated with the digital image interpretation to find rock distribution map which can be useful to get the information about water reservation potencial …


Photocatalytic Treatment Of Heavy Metal Waste Cr(Vi) Withtio2 Photocatalyst, Slamet Slamet, Riyadi Syakur, Wahyu Danumulyo Apr 2003

Photocatalytic Treatment Of Heavy Metal Waste Cr(Vi) Withtio2 Photocatalyst, Slamet Slamet, Riyadi Syakur, Wahyu Danumulyo

Makara Journal of Technology

Photocatalytic Treatment of Heavy Metal Waste Cr(VI) with TiO2 Photocatalyst. The photocatalytic reduction of hexavalent chromium/Cr(VI) using TiO2 and copper-doped TiO2 as photocatalysts have been studied in stirred tank and circulating photoreactors. All photocatalysts were characterized with FTIR (Fourier Transform Infra Red), BET (Brunauer-Emmett-Teller), XRD (X-Ray Diffraction) and SEM (Scanning Electron Microscope). TiO2 Merck and Degussa P-25 are the commercial photocatalysts used to compare the photocatalytic activity of all the prepared catalysts. Blank test experiments as well as the effect of dopants, EDTA (ethylenediaminetetraacetic acid) and activated carbon addition were studied. Cr(VI) reduction on various pH and initial Cr(VI) concentration …


Development And Analysis Of Geographic Information System For Electricity Network (Case Study: Surabaya Industrial Estate Rungkut In Surabaya)., Lilik Jamilatul Awalin, Bangun Muljo Sukojo Apr 2003

Development And Analysis Of Geographic Information System For Electricity Network (Case Study: Surabaya Industrial Estate Rungkut In Surabaya)., Lilik Jamilatul Awalin, Bangun Muljo Sukojo

Makara Journal of Technology

Development and Analysis of Geographic Information System for Electricity Network (Case Study: Surabaya Industrial Estate Rungkut in Surabaya). Geographic Information System (GIS) is a system of data which has spatial base. This may be cause has ability to process and analysis data quickly. The ability of GIS will be able to process the alternative in decision making. The need of electric power grows until recent time along with the existence of industrial sector expansion and land use expansion claim better service, large and balance stock of electric power. GIS is a solution for planning and managing data base system, for …


Application Of Remote Sensing And Geographic Information System Methods For Land Using Difference, Bangun Muljo Sukojo, Diah Susilowati Apr 2003

Application Of Remote Sensing And Geographic Information System Methods For Land Using Difference, Bangun Muljo Sukojo, Diah Susilowati

Makara Journal of Technology

Application of Remote Sensing and Geographic Information System Methods for Land Using Difference. Land using difference analysis has been done using remote sensing and Geographic Information System (GIS) methods. Identification of land using difference was conducted using map overlaying process of 1990s (digitized scalling 1:50.000) and 1997s land using map (interpreted from Landsat TM (Thematic Mapper) Image 1997) with UTM (Universal Transverse Mercator) coordinate. Image enhancement was done through histogram equalization with supervised classification devided into 7 classes: rice field, settlement, dry field, industry, pond, sport field and bush. Land using difference and river pollution BOD (Biological Oxygen Demand), COD …


Phase Composition Analysis Using Rietveld Methode And It's Influence To The Hardness Of Ti-Si-N Nanocomposites, Keba Moto, Lia Setiarini, Zufar Abubakar Apr 2003

Phase Composition Analysis Using Rietveld Methode And It's Influence To The Hardness Of Ti-Si-N Nanocomposites, Keba Moto, Lia Setiarini, Zufar Abubakar

Makara Journal of Technology

Phase composition analysis using rietveld methode and it’s influence to the hardness of Ti-Si-N nanocomposites. XRD data of nanocomposites Ti-Si-N have been analysed using GSAS based on Rietveld Method in order to identify phases and their composition as well as its influence on the hardness of these nanocomposites. Several new phases have been found in the sample beside the nc-TiN/a-Si3N4& a-/nc-TiSi2 that have been known widely. From the obtained crystalline phase, after the calculation of amorf Si3N4 and TiSi2 phase fraction, it is found that the optimum hardness can be reached when the fraction of a-Si3N4 phase around 8 wt.%


Influence Of Strain Rate And Temperature Of Hot Tension Testing On Mechanical Properties Of Medium Carbon Steel S48c, Dedi Priadi, Iwan Setyadi, Eddy S. Siradj Apr 2003

Influence Of Strain Rate And Temperature Of Hot Tension Testing On Mechanical Properties Of Medium Carbon Steel S48c, Dedi Priadi, Iwan Setyadi, Eddy S. Siradj

Makara Journal of Technology

Influence of Strain Rate and Temperature of Hot Tension Testing on Mechanical Properties of Medium Carbon Steel S48C. The characterization of S48C by hot tension testing was done to understanding the influence of temperature and strain rate for S48C flow stress, that close relationship with its forge ability. The hot tension testing was performed on temperatures and strain rates variation (T 850, 900, 950 0C and έ 0,01;1 s-1). The result of hot tension testing showed that increasing temperature decreases ultimate tensile strength (UTS) and flow stress of S48C. The higher decreasing of UTS is on 950 0C about 85% …


Study About High Influence Doping To Base Resistance And Bandgap Narrowing At Si/Si1-Xgex/Si Heterojunction Bipolar Transistor, Achmad Fadhol Apr 2003

Study About High Influence Doping To Base Resistance And Bandgap Narrowing At Si/Si1-Xgex/Si Heterojunction Bipolar Transistor, Achmad Fadhol

Makara Journal of Technology

Study About High Influence Doping to Base Resistance and Bandgap Narrowing at Si/Si1-xGex/Si Heterojunction Bipolar Transistor. Heterojunction is a link formed bedween two semiconductor materials and differend bandgap which has thinness under 50nm and grow the mixture of plate SiGe as bases. The link is an abrupt link or graded one. In this research learnt formulation of doping concentration influence to basis resistance and bandgap narrowing through Si/Si1-xGex/Si Heterojunction Bipolar Transistor with abrupt emitter-basis link, besides taking care to mobility and basis wide to basis resistance, it is also influence of mole fraction to bandgap power. From the result shows …


An Analytical Model For Calculating Bounds On Call Blocking Probabilities In Leo Satellite Networks, A. Hali̇m Zai̇m Jan 2003

An Analytical Model For Calculating Bounds On Call Blocking Probabilities In Leo Satellite Networks, A. Hali̇m Zai̇m

Turkish Journal of Electrical Engineering and Computer Sciences

We present an analytical model for calculating upper and lower bounds for call-blocking probabilities in a LEO satellite network that carries voice calls. The method is especially useful for large systems where calculation of call-blocking probabilities are too expensive. Our method calculates upper and lower bounds very easily and produces fairly accurate results.


The \Mathcal{H}_\Infty Model Matching Problem With One Degree Of Freedom Static State Feedback, Murat Akin, Ati̇lla Bi̇r Jan 2003

The \Mathcal{H}_\Infty Model Matching Problem With One Degree Of Freedom Static State Feedback, Murat Akin, Ati̇lla Bi̇r

Turkish Journal of Electrical Engineering and Computer Sciences

The aim of this paper is to develop a new approach for a solution of the continuous-time model matching problem by a static state feedback in the sense of \mathcal{H}_\infty optimality criterion by using Linear Matrix Inequalities (LMIs). The main contribution could briefly be described as to reformulate the model matching problem in LMI formulation, to present the solvability conditions and to give a design procedure for the one degree of freedom static state feedback control law. Finally, the results are applied to an example system.


A Full Adaptive Observer For Dc Servo Motors, Ata Sevi̇nç Jan 2003

A Full Adaptive Observer For Dc Servo Motors, Ata Sevi̇nç

Turkish Journal of Electrical Engineering and Computer Sciences

An adaptive observer estimating all parameters and load torque is proposed for DC servo motors. The observer uses no direct feedback but the adaptation schemes use current and speed measurements. Both the observer and adaptations are simple to implement for real-time applications. Simulation results are satisfactory for the full adaptive observer. If the observer works in parallel with only load torque and armature resistance adaptations, the results are very good even if very low-quality sensors are used. In this simulation, only a single hall sensor is used as a rotational transducer, which produces a single pulse per revolution, and very …


New Infratechnologies In The Deregulated Power Sector, Jordan Shikoski, Vladimir Katic, Risto Rechkoski Jan 2003

New Infratechnologies In The Deregulated Power Sector, Jordan Shikoski, Vladimir Katic, Risto Rechkoski

Turkish Journal of Electrical Engineering and Computer Sciences

This paper discusses new infratechnologies in the deregulated power sector. Most measurement and standardization techniques can be viewed as infratechnology. Infratechnologies are technical tools, including the measurement of data, test methods, and practices and technique. Standardization requirements are related to the measurement requirement. Although the system operation and market transactions concern many import aspects, they are insupportable and often complementary. This distinction between the technical and market information is important because the characteristics of information needs and the impact on economic efficiency and clean power are generally different. The present paper focuses on infratechnologies that can potentially increase the benefits …


Design Of A Tem-Cell With Increased Usable Test Area, Kresimir Malaric, Juraj Bartolic Jan 2003

Design Of A Tem-Cell With Increased Usable Test Area, Kresimir Malaric, Juraj Bartolic

Turkish Journal of Electrical Engineering and Computer Sciences

Transversal electromagnetic mode cells (TEM-cells) are used for electromagnetic compatibility measurements (emission and immunity), and for biomedical applications. Over the years, higher and higher frequencies are being used, which demands smaller transmission structures in order to obtain the homogeneous field distribution due to resonance. Such resonance destroys the TEM field, introducing higher order modes. The goal was to design the TEM-cell for GSM frequencies that will have a larger area with a homogeneous field used for testing, while still obtaining the characteristic impedance. Commercial TEM-cells used for frequencies of 900 MHz have only 2 cm in height available for testing, …


Initiatory Electrons In Compressed Gases In Positive Polarity, Mohammed Messaad, Mustapha Tioursi Jan 2003

Initiatory Electrons In Compressed Gases In Positive Polarity, Mohammed Messaad, Mustapha Tioursi

Turkish Journal of Electrical Engineering and Computer Sciences

This paper deals with the nature of seed electron sources in compressed N_2 for positive polarity. We present an experimental procedure that provides evidence of the fact that collisional detachment from negative ions plays the most important role in the supply of seed electrons. Conditioning phenomena in compressed SF_6, N_2 and air have been simulated under positive lightning impulses for point-plane geometry.


A New Simulator For Hvdc/Ac Systems-Part Ii, Baktiar Zangeneh, Abbas Shoulaie Jan 2003

A New Simulator For Hvdc/Ac Systems-Part Ii, Baktiar Zangeneh, Abbas Shoulaie

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a performance comparison (the focus of numerical simulation) of traditional simulation (TCS,TSE) with an optimal step time simulator (SOST) for large HVdc systems.In SOST, a Detailed simulation of HVdc converter behavior has been modified to include the automatic selection of optimal integration steps, frequency-dependent effects of an ac system, ac system phase and magnitude dynamics of voltage (particularly weak ac systems), control assessment and temporary over-voltage consequences. SOST, via graphical interfaces,provides fast and accurate information of electromechanical and the electromagnetic-transients behavior of a large HVdc/HVac system.


Improving The Security And Flexibility Of One-Time Passwords By Signature Chains, Kemal Biçakci, Nazi̇fe Baykal Jan 2003

Improving The Security And Flexibility Of One-Time Passwords By Signature Chains, Kemal Biçakci, Nazi̇fe Baykal

Turkish Journal of Electrical Engineering and Computer Sciences

While the classical attack of ``monitor the network and intercept the password'' can be avoided by advanced protocols like SSH, one-time passwords are still considered a viable alternative or a supplement for software authentication since they are the only ones that safeguard against attacks on insecure client machines. In this paper by using public-key techniques we present a method called signature chain alternative to Lamport's hash chain to improve security and flexibility of one-time passwords. Our proposition improves the security because first, like other public-key authentication protocols, the server and the user do not share a secret, thereby eliminating attacks …


Network Traffic Properties Of Bimodal Multicast Protocol, Öznur Özkasap, Mi̇ne Çağlar Jan 2003

Network Traffic Properties Of Bimodal Multicast Protocol, Öznur Özkasap, Mi̇ne Çağlar

Turkish Journal of Electrical Engineering and Computer Sciences

The popularity of large-scale distributed applications, such as videoconferencing, multimedia dissemination, electronic stock exchange and distributed cooperative work, has grown with the availability of high-speed networks and the expansion of the Internet. The key property of this type of applications is the need to distribute data among multiple participants together with an application-specific quality of service needs. This fact makes scalable multicast protocols an essential underlying communication structure. Although there exist several studies investigating the traffic characteristics of unicast communication, multicast traffic has not been examined extensively in previous studies. It is well known that the aggregate traffic properties of …


New Approaches For On-Line Tuning Of The Linear Sliding Surface Slope In Sliding Mode Controllers, Sezai̇ Tokat, İbrahi̇m Eksi̇n, Müjde Güzelkaya Jan 2003

New Approaches For On-Line Tuning Of The Linear Sliding Surface Slope In Sliding Mode Controllers, Sezai̇ Tokat, İbrahi̇m Eksi̇n, Müjde Güzelkaya

Turkish Journal of Electrical Engineering and Computer Sciences

The main objective of this study is to propose new approaches for on-line tuning of the linear sliding surface slope in sliding mode controllers. The new approaches are developed for a class of second order systems on new coordinate axes, one of which is the classical sliding surface and the other one is naturally chosen to be orthogonal to it. The control input of the sliding mode control law is then modified accordingly by applying the Lyapunov stability condition. The adjustment of the linear sliding surface slope defined in the new coordinate axes is achieved by tuning a new parameter …


Zero-Crossing Based Demodulation Of Minimum Shift Keying, Mi̇ne Kalkan, Feza Keresteci̇oğlu Jan 2003

Zero-Crossing Based Demodulation Of Minimum Shift Keying, Mi̇ne Kalkan, Feza Keresteci̇oğlu

Turkish Journal of Electrical Engineering and Computer Sciences

Minimum shift keying (MSK) modulation has features such as constant envelope, compact spectrum and good error performance, which are all desirable in many digital applications including mobile radio. Numerous receiver structures to demodulate MSK have been suggested, such as correlation receivers, differential detectors and frequency discriminators. MSK is a form of biphase keying and can be detected by a zero-crossing based phase demodulator which gives near optimum performance. In this paper, the bit error performance of a zero-crossing based coherent MSK demodulator is theoretically investigated and a closed-form expression for the bit error rate is derived. The results indicate that …