ITS       HomeSearch       ITSOffice of Telecommunications OT Report 76-97Spectrum Resource Assessment in the 2.7 to 2.9 GHz       BandPhase II: Measurements and Model ValidationAugust 1976Robert L. Hinkle, Robert M. Pratt, and Robert J. Matheson
Abstract: The Office of Telecommunications (OT)       undertook a detailed program to measure and analyze spectrum utilization       in the 2.7 to 2.9 GHz band in the Los Angeles and San Francisco areas in       support of an Office of Telecommunications Policy (OTP) Spectrum Resource       Assessment task. The measurement program consisted of on�site visits to       compare predicted and actual PPI interference patterns, and utilization of       the Radio Spectrum Measurement System (RSMS) van to validate the component       models used in predicting radar�to�radar interference.

From the measured data and a supporting literature search, it was       concluded that ducting and man�made clutter (building attenuation) should       be included in the propagation loss predictions in order to improve the       prediction accuracy of radar�to�radar interference and radar frequency       assignments. Even though potential multipath wave interference conditions       can be identified, to account for this analytically would require an       extremely complex antenna and terrain model. Due to modeling inaccuracies,       the difference between the predicted and actual radar�to�radar       Interference�to�Noise Ratio (INR) levels may be as large as 22 dB (2s       standard deviation region). However, INR errors of approximately 25 dB can       still result in relatively accurate predictions of interference patterns       on the victim PPI display for conditions where mainbeam�to�backlobe       antenna coupling predominates. In summary, it was concluded that the       analytical radar�to�radar interference techniques used in this       investigation can be used to predict interference patterns on the victim       radar PPI display with sufficient accuracy to allow assessment of radar       band congestion, frequency assignment flexibility, and potential of the       band to absorb new users.

Keywords: radar; interference; measurements; model       validation
-  Title         Page; Statement of Mission; Preface, Acknowledgement; Table of Contents;         Abstract 
-  Section         1: Introduction 
-  Section         2: Findings and Recommendations 
-  Section         3: Interference Prediction Technique 
-  Section         4: Los Angeles Area Investigation 
-  Section         5: San Francisco Area Investigation 
-  Appendix         A: Antenna Characteristic Modeling 
-  Appendix         B: Emission Spectrum Modeling and Measurements 
-  Appendix         C: Frequency�Dependent�Rejection 
-  Appendix         D: Propagation Loss 
-  Appendix         E: Detailed Measurements 
-  Appendix         F: Los Angeles and San Francisco Area Measurement Plan 
-  Appendix         G: RSMS Van Measurements 
-  References 

Disclaimer: Certain commercial equipment, components,       and software are identified in this report to specify adequately the       technical aspects of the reported results. In no case does such       identification imply recommendation or endorsement by the National       Telecommunications and Information Administration, nor does it imply that       the equipment or software identified is necessarily the best available for       the particular application or uses.

For technical information concerning this report,       contact:Frank Sanders, Division Chief, Telecommunications       Theory Divison (ITS.T)Institute for Telecommunication       SciencesVoice: (303) 497-7600fsanders@its.bldrdoc.gov
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