has unique physical properties that demand observation when interference is absent. Unless these issues are addressed in a timely manner, the effectiveness and utility of EESS will likely be increasingly compromised, particularly as wireless services and unlicensed devices proliferate. Most problematic are future ubiquitous unlicensed ultrawideband consumer devices that can proliferate without limit.

Box 2.3 illustrates a sporadic record of achievement in appropriately allocating spectrum and/or coordinating technology development between EESS and competing active services. A technology advisory body, incorporating members from all relevant services, could help mitigate such failures. Such an entity would link EESS and other relevant active and passive communities in an early identification of issues and opportunities regarding competing spectral needs and shared standards development. Such a holistic body would supplement the more adversarial and segmented bodies that currently provide most such advice.

BOX 2.3

Illustrative Examples of Successes and Failures in Frequency Coordination That Affect the Earth Exploration-Satellite Service (EESS)


  • European and Japanese transition to 77 GHz band for automobile radar, avoiding 23-24 GHz.

  • The development of airborne sub-band-based radio frequency interference (RFI) mitigation methods that delete single strong interference signals, although not weak or diffuse interference.

  • The International Telecommunication Union trade-off of allocations to obtain stronger protection at more important bands at 50-57 GHz.

  • The migration of new instrument specifications toward protected bands (Advanced Technology Microwave Sounder, Special Sensor Microwave/Imager, Special Sensor Microwave/Imager Sounder, Conical Microwave Imager Sounder, and Microwave Imager/Sounder).


  • The lack of engagement between the auto radar community, Earth Exploration-Satellite Service (EESS), and regulators during the technology’s early development.

  • The lack of accepted remedies when unlicensed devices producing limited EESS interference multiply in numbers so as to collectively damage EESS and other services.

  • The lack of global exclusive EESS allocations at 18.7 and 10.65 GHz; critical bands experiencing RFI.

  • No allocation of a protected band at C-band.

  • The difficulty in effectively employing lower-frequency bands (e.g., 1400-1427 MHz) owing to RFI; apparent inadequate protection for EESS operation in the exclusively passive 1400-1427 MHz band.

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