1 / 18

PLL Implementation with Simlink and Matlab

PLL Implementation with Simlink and Matlab. Project 2 ECE283 Fall 2004. Simulink in MATLAB. Graphic user interface Continuous, discrete, and mixed mode Integration with MATLAB Fast prototyping User-defined functions How to run it >>simulink Or click simulink icon. Simulink main screen.

avari
Download Presentation

PLL Implementation with Simlink and Matlab

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. PLL Implementation with Simlink and Matlab Project 2 ECE283 Fall 2004

  2. Simulink in MATLAB • Graphic user interface • Continuous, discrete, and mixed mode • Integration with MATLAB • Fast prototyping • User-defined functions • How to run it • >>simulink • Or click simulink icon Simulink main screen

  3. Graphic User Interface • Make a new model window • Expand library • Drag and drop • Connect blocks • Simulate • Visualize • Tuning Simulink built-in library

  4. Make a model • New model • Open library • Drag blocks • Connect • Source and sink • Example:AmModEx.mdl Amplitude modulation

  5. Simulation • Tune • Simulation time • Relative tolerance • Refine factor • Etc • Simulate • Example:AmModEx.mdl Simulation parameters

  6. Visualization • Double click scope • Options on signal source and sink • External files • Workspace variables • Example:AmModEx.mdl Simulation output scope

  7. Subsystem • Subsystem for modular programming • How to make it • Subsystem library • Subsystem conversion • Example:AmModEx.mdl Ports and subsystem library Triggered subsystem

  8. Getting Help • Need help? • MATLAB and Simulink help • Mathworks user community • Mathwork technical support Simulink help screen

  9. PLL Implementation • Sampler • Voltage controlled clock • Voltage controlled oscillator • Feedback loop Decision-directed phase-locked loop

  10. Sampler • Options • Triggered subsystem • User-defined function • Others • Latched and unlatched • Matters with discrete-time signals • Almost same with continuous-time signals except for feedback • Example:TriggerEx1.mdl • Subsystem examples Latched and unlatched trigger example

  11. Integration • Initiailization • Matched filter • Correlator • External triggering • Example:IntegratorEx.mdl Integration block parameters

  12. S-function • User-defined function written in MATLAB, etc. • One input and one output • scalar, vector, matrix, etc. • Static parameters • R14 provides more options for user-defined function User-defined functions library

  13. S-function Operation • Initialization • Calculate outputs • Update discrete states • Calculate derivatives • Integration • Calculate outputs • Calculate derivatives • MATLAB example code sfuntmpl.mis in matlabroot/toolbox/simulink/blocks S-function operation diagram

  14. Example Code function [sys,x0,str,ts] = VCO(t,x,u,flag,FreqCntr) %VCO switch flag, case 0,% Initialization [sys,x0,str,ts]=VCOInit; case 1,% Derivatives sys=VCODeriv(t,x,u); case 2,% Update sys=VCOUpdate(t,x,u); case 3,% Outputs sys=VCOOutput(t,x,u,FreqCntr); case 4,% GetTimeOfNextVarHit sys=VCPNextHit(t,x,u); case 9,% Terminate sys=VCOExit(t,x,u); otherwise % Unexpected flags End Flag 0: Initialization Flag 1: Calculation of derivatives Flag 2: Update of discrete states Flag 3: Calculation of output Flag 4: Calculation of next sample hit Flag 9: End of simulation tasks

  15. S-function Initialization function [sys,x0,str,ts]=VCOInit sizes = simsizes; sizes.NumContStates = ; sizes.NumDiscStates = ; sizes.NumOutputs = ; sizes.NumInputs = ; sizes.DirFeedthrough = ; sizes.NumSampleTimes = ; % at least one sample time is needed sys = simsizes(sizes); x0 = []; % initialize the initial conditions str = []; % str is always an empty matrix ts = [0 0]; % initialize the array of sample times Define necessary Internal states (continuous and discrete-time) Number of inputs Number of outputs Initial conditions

  16. S-function Output function [sys,x0,str,ts] = VCO(t,x,u,flag,FreqCntr,Phase,Gain) switch flag, …………… case 3,% Outputs …………… sys=VCOOutput(t,x,u,FreqCntr,Phase,Gain); End …………… function sys=VCOOutput(t,x,u,FreqCntr,Phase,Gain) sys = Gain*cos(2*pi*(FreqCntr+u)*t+Phase); T: time X: state U: input Flag: computation mode Static parameters

  17. S-function Instantiation • Drag and drop S-function system block to a model • Double click the block to specify the script name and static parameters • Example: VCOSfuncEx.mdl S-function instance S-function block parameters

  18. Discussions on PLL • Modulation frequency • Number of waves per symbol • Low-pass filter • Simulation length • Symbol feedback delay • Evaluation • Timing error • Capture range • Loop lock range • Effect of symbol error • Effect of signal noise Decision-directed PLL diagram

More Related