Application of the Four Variable Model to a CAD System for Microwave Communications Devices

1、APPLICATION OF THE FOUR VARIABLE MODEL ii APPLICATION OF THE FOUR VARIABLE MODEL TO A CAD SYSTEM FOR MICROWAVE COMMUNICATIONS DEVICES by Yun Zou, B.Sc., M.Sc., (Wuhan University of Technology) M.Eng. (McMaster University) A Thesis Submitted to the School of Graduate Studies in Partial Fulfillment of

2、 the Requirements for the Degree Master of Engineering McMaster University iii MASTER OF ENGINEERING (2000) McMaster University (Computer Engineering) Hamilton, Ontario TITLE:Application of the Four Variable Model to a CAD System for Microwave Communications Devices AUTHOR: Yun Zou, B.Sc., M.Sc., M.

3、Eng. SUPERVISOR: Dr. David L. Parnas, Professor of Computing and Software NUMBER OF PAGES:x, 170 iv ABSTRACT The four variable model was successfully applied to the water level system, a simple and practical real-time control system van Schouwen90. In this work, the application of the four-variable

4、model to the CAD system for microwave communications systems (CADMCS), a complex non-real-time software package, has been studied. The documentation of the complete system requirements for the CADMCS system has been presented. The four variable model has been reviewed in detail. Based on the charact

5、eristics of CAD systems, the techniques to control the complexity using the well-known principles such as information-hiding, separation of concerns or divide-and-conquer have been discussed. The use of well-known mathematical concepts such as vectors, vector functions, as well as geometry objects a

6、s the types of the monitored and controlled variables has been demonstrated. New types of the variables are also introduced to abstract application domain objects and to serve as the mechanism to support a hierarchical system structure. The recursive decomposition of the monitored and controlled var

7、iables has been demonstrated in this work. Relational algebra has been applied to presenting and organizing the REQ (requirements) relation in the CADMCS system. It has been shown how complex relations can be described in terms of simpler sub-relations by the decomposition operator in the relational

8、 algebra. v ACKNOWLEDGEMENT I would like to express my sincere thanks to Dr. David L. Parnas for his guidance, insight and support throughout the preparation of this thesis. I would like to thank Dr. Chen Wu, Mr. Patrick Yau, Mr. Yan Zhang for the long helpful discussions about the domain expertise

9、involved in the CADMCS system and their reviewing of the system requirements document as well as for their donations of the related programs and document. I would also like to thank Dr. Tom Luo and Dr. Martin von Mohrenschildt for their helpful comments and suggestions after reading the thesis. I wo

10、uld like to thank Dr. Anthony Petric and Dr. Alex Zhang for voluntarily helping to improve the quality of the thesis from the technical presentation point of view. My appreciation goes to the staff members Doris Burns and Cheryl Gies for their help with administrative matters during my work on this

11、thesis. Finally, I would like to acknowledge the financial support of the Natural Sciences and Engineering Research Council of Canada, Bell Canada, The Telecommunications Research Institute of Ontario (TRIO/CITO). vi TABLE OF CONTENTS ABSTRACT . iii ACKNOWLEDGEMENT iv TABLE OF CONTENTS . vi CHAPTER

12、1 INTRODUCTION . 1 Section 1 Why a Software Requirements Document Is Needed 1 Section 2 What Are Software Requirements? 3 Section 3 The Four-Variable Model . 4 3.1. Introduction. 4 3.2. The Four Variables . 6 3.3. The Relation NAT . 10 3.4. The Relation REQ . 11 3.5. The Relation IN . 12 3.6. The Re

13、lation OUT . 12 3.7. Contents of System Requirements Document 13 3.8. Contents of System Design Document . 13 3.9. Software Behaviour Document . 14 Section 4 Why Apply the Four-Variable Model to a CAD System? 15 vii 4.1. Real-Time vs. Non-Real-Time 15 4.2. Is the Four-Variable Model Practical for a

14、CAD System?. 19 4.3. Why the CADMCS System? . 20 Section 5 The Scope of the Thesis . 21 CHAPTER 2 MATHEMATICS BACKGROUND . 23 Section 1 Why This Chapter Is Needed? . 23 Section 2 Relational Algebra . 24 2.1. Relations and Functions . 24 2.2. Relational Algebra . 27 2.3. Graphical Notation . 34 Secti

15、on 3 Review of Vector Analysis . 39 Section 4 Geometry Review 44 Section 5 Review of the Tabular Notation . 50 5.1. Introduction . 50 5.2. Terminology in Tables . 51 5.3. Normal Tables . 52 5.4. Vector Tables . 53 5.5. Mixed Vector Tables . 53 CHAPTER 3 DISCUSSION OF THE APPLICATION OF THE FOUR VARI

16、ABLE MODEL TO A CAD SYSTEM 55 Section 1 Description of the CADMCS System . 55 viii Section 2 Conquering Complexity 57 Section 3 The Monitored and Controlled Variables in the CADMCS System . 58 Section 4 The Relation REQ . 64 4.1. System Mode and REQ Relation Partition . 64 4.2. REQE Relation. 66 4.3

17、. REQI Relation . 67 4.4. REQP Relation . 67 Section 5 System Design Document . 69 CHAPTER 4 SUMMARY AND FUTURE WORK . 71 REFERENCES . 74 APPENDIX A THE SYSTEM REQUIREMENTS OF A CAD SYSTEM FOR MICROWAVE COMMUNICATIONS DEVICES USING THE FOUR-VARIABLE MODEL . 78 Chapter A1 The Monitored Variables . 78

18、 Section 1 Physical Variables (ME) . 78 1.1. Known Actual Values (MK) . 79 1.2. Unknown Actual Value (MR) . 91 Section 2 System Status Variables (MI) . 94 2.1. Requesting Customizing Parameters . 94 2.2. Status Except for Requesting Customizing Parameters. 96 ix Section 3 Monitored Parameters (MP) .

19、 99 Chapter A2 The Controlled Variables . 103 Section 1 Computed Values (Cc) . 103 Section 2 Messages (CM) 106 2.1. Customizing Parameters . 106 2.2. Status Messages Except for Customizing Parameters . 109 Section 3 Controlled Parameters (Cp) 110 Chapter A3 NAT and REQ Relation . 114 Section 1 NAT R

20、elation . 114 Section 2 System Mode and REQ Relation Partition . 114 2.1. Mode Definitions 114 2.2. Mode Transition Table 115 2.3. REQ Partition and Decomposition . 115 Section 3 REQE Relation . 116 3.1. REQEI . 116 3.2. REQEO . 117 Section 4 REQI Relation . 124 Section 5 REQP Relation . 130 Chapter A4 MACROS, PREDICATES AND FUNCTIONS 132 Section 1 Macro Definitions . 132 x Section 2 Predicate Definitions . 135 Section 3 Function Definitions . 138 CHAPTER A5 CONSTA