User`s guide

Agilent E5505A User’s Guide 7
Figure 74. Reference source noise approaches DUT noise 111
Selecting a Reference 112
Figure 75. DUT noise approaches reference noise 112
Using a Similar Device 112
Using a Signal Generator 113
Tuning Requirements 113
Table 12. Tuning Characteristics of Various VCO Source Options 113
Figure 76. Voltage tuning range limits relative to center voltage of the VCO tuning
curve 114
Estimating the Tuning Constant 115
Table 13. VCO tuning constant calibration method 115
Tracking Frequency Drift 116
Evaluating beatnote drift 116
Changing the PTR 118
Figure 77. Peak tuning range 118
The Tuning Qualifications 118
Minimizing Injection Locking 120
Adding Isolation 120
Increasing the PLL Bandwidth 120
Figure 78. Peak tuning range (PTR) Required by injection locking. 121
Inserting a Device 122
An attenuator 122
Figure 79. Measurement noise floor relative to R-Port signal level 122
An amplifier 123
Figure 80. Measurement noise floor as a result of an added attenuator 123
Evaluating Noise Above the Small Angle Line 124
Determining the Phase-Lock-Loop bandwidth 124
Figure 81. Phase lock loop bandwidth provided by the peak tuning range 125
Figure 82. Graph of small angle line and spur limit 126
Figure 83. Requirements for noise exceeding small angle limit 127
6 Absolute Measurement Examples
Stable RF Oscillator 130
Required equipment 130
Defining the measurement 130
Figure 84. Select the parameters definition file 130
Figure 85. Enter source information 131
Table 14. Tuning characteristics for various sources 132
Selecting a reference source 132