The prospective user must describe the proposed use of the DCS for 

 examination by the NESS DCS Review Committee, which recommends 

 appropriate action to be taken by the Director of NESS on the 

 request. A questionnaire (see Appendix A) is provided to facilitate 

 presentation of information needed to properly consider the user's 

 request . 



Upon approval of the user's request for participation in the DCS, 

 a Memorandum of Agreement will be prepared to detail the rights and 

 responsibilities of both NESS and the participating user. This 

 agreement is attached as Appendix B. 



1.2.2 What Does It Cost? 



Collection of data from user sensor platforms and processing the data 

 for dissemination using the GOES DCS facilities is without charge to 

 the user. The user will be responsible for his own costs of sensor 

 platforms, such as procurement, maintenance, and installation, 

 and such tests as are required to establish conformity to the DCS 

 performance specifications. The user will also be responsible for 

 the costs of communications lines, modem equipment, and data terminals 

 necessary to the dissemination capability of the GOES/DCS. Unless an 

 exception is justified, data collected for individual users will be 

 made available by NESS to other users or interested parties upon request. 



1.2.3 What Geographical Coverage Is Provided by the DCS? 



The DCS was based on the practicality of an Earth-sited transmitter 

 operating with a suitable antenna to provide an Effective Isotropic 

 Radiated Power (EIRP) of 50 dBm (max. ) at a minimum antenna elevation 

 angle of less than 5°. The minimum antenna elevation angle defines 

 the portions of the Earth's surface having geocentric angles up to 

 approximately 77°, measured from the subsatellite point. Figure 

 1 described the geometry of the DCS. Figure 2 presents the actual 

 Earth surface coverage for the DCS of both GOES satellites. 



1.2.4 What Is the DCS Message Capacity? 



Access to the spacecraft transponder is shared among all platform site 

 transmitters within its field of view. (See Figure 2.) The DCS has the 

 capacity for handling at least 10,000 transmissions (30-s average 

 message duration) from platform sites via the spacecraft transponder 

 in each 1-hour period. Frequency division multiple access with time- 

 shared channel occupancy is the technique used to meet the data traffic 

 requirements. 200 channels are available for domestic user assignment 

 with an additional 33 channels provided for cooperative working with 

 international users. The channel spacing accommodates the 100-bits-per- 

 second DCS message data rates. 



1.2.5 What Type of User Sensor Platform Can Be Used? 



The simplest user platform configuration requires: 



(1) An UHF transmitter and antenna combination capable of producing 

 +50 dBm EIRP. 



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