CONTENTS

 1     Introduction and background 
        1.1     Introduction 
        1.2     Background 
 2     Scatterometers
        2.1     Use of the band near 13.5 GHz for scatterometers
        2.2     Bandwidth requirements 
        2.3     Feasibility of using other bands 
        2.4     Long-term need for operation around 13.5 GHz for scatterometers
 3     Altimeters 
        3.1     Use of the band near 13.5 GHz for altimeters 
        3.2     Bandwidth requirements 
        3.3     Feasibility of using other bands 
        3.4     Continued need for frequencies around 13.5 GHz for altimeters 
 4     Precipitation radars (PR)
        4.1     The use of band near 13.5 GHz by PR  
        4.2     Bandwidth requirements 
        4.3     Feasibility of using other bands 
                  4.3.1     Measurement dynamic range 
                  4.3.2     Instantaneous field of view (IFOV)
                  4.3.3     Signal-to-clutter ratio (S/C)
                  4.3.4     Frequencies for dual-band radars 
        4.4     Continued need for operation around 13.5 GHz 
 5     Summary and conclusions