The Implementation of A Simulation Environment For Mobile Communication Is VeryrnSignificant For Engineers And Researchers of A Mobile Communication Since It Enables ThemrnTo Work In A Environment That Is Almost Similar With The Practical One. BecausernMultipurpose Programmable Digital Signal Processing Have Made It Possible To ImplementrnDigital Communication Like Modulators And Demodulators Completely In Software.rnThe Aim Of This Project Work Is To Create And Verify A Channel Model For A Mobile RadiornChannel. This Model Will Later Be Used In The Project To Simulate Digital Transmission OfrnData Through A Source(Speech) Coder, Channel Coder And The Modulator.rnWhen Radio Systems Are Simulated It Is Usually Not Practical To Simulate The BandpassrnCarrier Signals. The High Sampling Frequency Leads To Unnecessarily Long Simulation Time.rnInstead We Use An Equivalently Complex Low Pass-Model Of The Whole System.rnThis Study Was Designed In Such A Way That First The Detail BackgroundrnTheory Of The Subject Matter Is Discussed In With Alternative Means OfrnApproaching The Subject Matter And Why One Technique Is PreferredrnAmongst Existing Techniques Is Discussed After Mathematical AndrnLogically Presenting Of The Efficiency And Effectiveness Of ThernTechnique. The Chosen Technique Will Be Discussed In Detail And ArnSoftware Algorithm Is Formulated.rnChapter 1 Presents Radio Propagation Path Loss, Link-Budgets And LogrnNormal Shadowing And Describes A Way To Model And Predict The Fading,rnTime Delay Spread And Dopler Spread And Describes How To Measure AndrnModel The Impact That Signal Bandwidth And Motion Have On ThernInstantaneous Received Signal Through The Multipath Channel Of RadiornPropagation In Many Operating Environments. The Various CharacteristicsrnThat Produce And Affect The Channel Will Be Simulated Using The SpectrumrnMethod.rnChapter 2 Provides An Introduction To Speech Coding. The Goal Of SpeechrnCoding Systems Is To Transmit Speech With The Highest Possible QualityrnUsing The Least Possible Channel Capacity. Linear Predictive CodingrnTechniques Are Simulated In This Thesis.rnChannel Coding, Error Control Coding And Interleaving Are Presented InrnChapter 3 For Error Correcting Capability That Resist Mobile ChannelrnImpairments. Amongst These Interleaving And Reed-Solomon Coding AndrnDecoding Are Discussed For Software Simulation.rnVrnChapter 4 Covers The Most Common And Bandwidth Efficient DigitalrnModulation Techniques Used In Wireless Communications And DemonstratesrnThe Tradeoff That Must Be Made In Selecting A Modulation Technique. IrnTried To Simulate The Bandwidth Efficient And Error Prone P/4rnDifferential Quadratic Phase Shift Keying Modulation Scheme(Qpsk) AndrnCompared For Performance With The Binary Phase Shift Keying And ThernFamous And Efficient Gsm Modulation Technique The Gausian Minimum PhasernShift Keying(Gmsk).rnThere Are A Number Of Factors That Enter Into The Choice Of A ModulationrnScheme For Use InrnA Wireless Application. Performance Of A Cellular System Is Dependent On The Efficiency OfrnThe Modulation Scheme Employed. Constant Envelope Modulation Techniques,rnSuch As Qpsk And Gmsk, Will Be Used To Examine The Features Of Each Scheme AndrnIllustrate Their Uses In The Cellular Environment. The Study Of Qpsk And Gmsk Is CrucialrnTo Second And Third Generation Cellular Systems Where Achieving High Capacity Is ThernSupreme Factor. The Goal Of A Modulation Technique Is Not Only To Transport A MessagernSignal Through A Radio Channel, But To Achieve This With The Best Quality, Power Efficiency,rnAnd The Least Amount Of Bandwidth Possible. In Order To Study The Techniques ForrnOccupying Less Bandwidth And Reducing Power Consumption Per Channel, A Closer Study OfrnTransmission Techniques Are Explored In Order To Determine A Favorable ModulationrnTechnique For A Particular Wireless Application.rnIn Portable Radio Systems Where People Communicate While Walking OrrnDriving, These Methods Are Used Individually Or In Tandem To ImprovernThe Quality (I.E Speech Coding Reduce The Bit Error Rate) Of DigitalrnMobile Radio Communications In The Presence Of Fading And Noise.