Microwave attenuation measurement

Description

;Cover Title Copyright Preface Contents Principal symbols 1 Introduction 2 Basic Definitions and equations related to attenuation 2.1 Insertion loss and attenuation 2.2 Reflective and dissipative components of attenuation 2.3 Substitution loss 2.4 Transducer loss 2.5 Voltage loss 2.6 Network efficiency 2.7 Available power transmission factor 2.8 Mismatch loss factor 2.9 Cascaded 2-ports 2.10 Measurement of the substitution loss of a variable attenuator between isolators 2.11 Mismatch error and uncertainty 2.12 Leakage 2.13 References 3 D.C., a.f. and i.f. attenuation standards 3.1 Kelvin-Varley voltage dividers 3.2 Inductive voltage dividers 3.2.1 Introduction 3.2.2 Construction of inductive voltage dividers 3.2.3 Basic theory related to inductive voltage dividers 3.2.4 Errors in inductive voltage dividers 3.2.5 Error when two multi-decade inductive voltage dividers are connected in tandem 3.2.6 Two stage inductive voltage dividers 3.2.7 Conclusions 3.3 I.F. piston attenuators 3.3.1 Introduction 3.3.2 Theory of the piston attenuator 3.3.3 Excitation and purity of mode 3.3.4 Design considerations 3.3.5 Summary of sources of error 3.4 References 4 Microwave attenuation standards 4.1 Rotary vane attenuator 4.2 Microwave piston attenuators 4.2.1 Introduction 4.2.2 Representative piston attenuator designs 4.2.3 Piston attenuator as an absolute standard 4.3 References 5 Power radio methods for measuring attenuation 5.1 Straight-forward single power meter method 5.2 Dual channel power ratio method 5.3 Systems using amplitude stabilisation of the source 5.4 Automated power ratio attenuator calibrators 5.5 References 6 R.F. substitution References 7 I.F. substitution 7.1 General 7.2 Frequency conversion 7.3 Errors and their reduction in the series method 7.4 Errors and their reduction in the parallel method 7.5 Comments on various present-day i.f. substitution systems 7.6 References 8 A.F. substitution 8.1 A.F. substitution systems using bolometers as square law detectors 8.2 A.F. substitution system using at NRC 8.3 Modulated sub-carrier attenuator calibrators 8.3.1 Introduction 8.3.2 Detailed description of the RRE modulated sub-carrier system 8.3.3 Errors in a modulated sub-carrier attenuator calibrator 8.3.4 Special techniques for measuring high-values of attenuation with a modulated sub-carrier system 8.3.5 Automatic calibration of rotary vane attenuators on a modulated sub-carrier system 8.4 References 9 Determination of low values of attenuation from reflection coefficient measurements 9.1 Method using a standing-wave indicator 9.2 Method using reflectometer 9.3 Conclusion 9.4 References 10 Swept frequency techniques 10.1 Introduction 10.2 Components for swept frequency systems 10.2.1 Swept sources 10.2.2 Broadband detectors 10.2.3 Directional couplers 10.2.4 P-I-N diode levellers 10.2.5 Ratiometers 10.3 Swept frequency attenuation measuring equipment 10.4 Conclusions 10.5 References 11 Microwave network analysers 11.1 Introduction 11.2 Descriptions of network analysers 11.3 Elimination of internal systematic errors 11.4 Other calibration procedures 11.5 Errors arising in a microwave network analyser 11.6 Evaluation of uncertainties 11.7 Conclusions 11.8 References 12 Other methods of measuring microwave attenuation 12.1 Laverick's three channel technique 12.2 Peck's self-calibration technique 12.3 Two-channel null method 12.4 Single-oscillator shuttle pulse method 12.5 Determination of attenuation from Q measurements 12.6 Determination of attenuation with a shorted slotted line 12.7 Somlo's fixed-probe method for measuring localised waveguide attenuation 12.8 Attenuation measurement with two thermistors in adjacent arms of a Wheatstone bridge 12.9 Method using a Josephson junction in a superconducting loop 12.10 Miscellaneous methods 12.11 References 13 Attenuation transfer standards 13.1 Introduction 13.2 Directional coupler transfer standards 13.3 Directional coupler waveguide switch transfer standards 13.4 Side-arm-switched directional coupler transfer standards 13.5 Variable waveguide attenuator transfer standards 13.6 Coaxial attenuator transfer standards 13.7 References 14 Elimination of error and determination of uncertainty 14.1 Introduction 14.2 Errors and uncertainties 14.3 Application of probability 14.4 Uncertainty arising from systematic error associated with multiple reflections 14.5 Combination of uncertainties and expression of the result 14.6 Example of determination and expression of uncertainty 14.7 References 15 Conclusions 15.1 Review of present-day techniques 15.2 Future developments 15.3 References Appendixes 1 Scattering parameters 2 Signal flow graphs 3 Evanescent electromagnetic fields inside a perfectly conducting cylinder 4 Combined effect of end vane misalignment and insufficient central vane attenuation on the performance of a rotary vane attenuator 5 Square law deviation of a bolometer 6 Error due to noise when measuring attenuation with a modulated sub-carrier system 7 Bilinear transformation of a circle in the complex plane 8 Theory of weakly connected superconducting rings Index