Commercial Communications Satellite, January 1960

Editor’s note:  The Hughes Report presented below along with the attached NASA commentary can be found in NASA SP-4407, Volume III, 1995.

By the end of 1959, Harold A. Rosen and his team had reworked their initial mid-1959 design for a geosynchronous communications satellite into a form that was very close to what was actually first launched as Syncom 1 in 1963. This report describes that design; only relevant excerpts appear here. The report anticipated a NASA program for communications satellite research and development that might provide a source of funding to Hughes for developing the satellite; however, NASA first chose to support a lower orbit satellite proposed by RCA called Relay. During discussions with NASA in 1960, the space agency suggested to Hughes the use of a larger Thor Delta booster rather than the Scout booster specified in this report. This would allow the satellite to be launched from Cape Canaveral in Florida rather than the Jarvis Island launch site discussed in the report.

Commercial Communications Satellite 

Report RDL/B-1, Engineering Division

H.A. Rosen and D.D. Williams,

Hughes Aircraft Company

January 1960.

 

1. INTRODUCTION – PROGRAM OBJECTIVES

This document describes an inexpensive communication satellite system for inter- continental transmission of television, telephonic, and teletype messages on a commercial basis.

The system proposed uses an active repeater in a satellite having a circular orbit in the plane of the earth’s equator with a period of 24 hours. Such a satellite is generally recognized as the ultimate communication satellite because it remains stationary to the earth.  The NASA has a program which is expected to lead eventually to such a satellite. The schedule for the program is not firm, but NASA testimony to Congress indicates that the goal is four to five years away. This conclusion is reached from the technical specifications that NASA has until now believed are necessary, involving heavy (800 to 3000 pounds), complex payloads with two to three years’ life as an objective. As a more immediate pro- gram, NASA will put a number of 100-foot diameter passive balloon reflectors into orbit during this year. These balloons will be tracked by several organizations, and will provide valuable scientific information. However, such reflectors are not of any real commercial value because [of] large amounts of power per unit bandwidth and immense tracking antennas required to give even the intermittent coverage afforded by low-altitude orbits.

There are several military communication satellite programs now under way. None of these conflict with the commercial program proposed here; the military programs use high power active repeaters in low-altitude orbits in order to avoid any requirements for large antennas at the terminals.

The presently proposed commercial system can be put into operation within one year. This radical improvement in schedule is achieved primarily through the design of a very light (25 pound) satellite repeater, a design based on realistic objectives for satisfactory commercial application. The light payload required with the present concept permits use of an inexpensive solid-propellant booster, the Scout. This results in a program cost of 5 million dollars.

The advantages of such a program would be several fold. Financially, it is believed that the initial development, terminal installations, and launching costs could be recovered in a fraction of the first year’s operation. It is expected that the useful life of a repeater will be about one year, and that the cost of replacing the repeater in orbit will be about 0.5 million dollars.

The suggested communication system is capable of large growth. The first repeater will cover most of the continental United States, all of Europe, all of South America, and much of Africa. An additional repeater would cover Hawaii, Australia, Japan, and other parts of the Orient. In addition to extension of geographic coverage, the existence of the communication link will result in an increase in foreign business which in turn will result in greater use of the facility. Extrapolation of recent trends in overseas messages shows that the present cable capacity between the U.S. and Europe will be exceeded within the next two years. Since the proposed facility is much less expensive than a cable, it is logical to expect this overflow to be handled by the proposed facility.

In addition to its commercial value, the proposed communication satellite should contribute greatly to national prestige and friendly foreign relations.

2. SUMMARY OF TECHNICAL FEATURES

The proposed communication system consists of a satellite repeater in a synchronous, equatorial orbit operating in conjunction with two or more ground terminals, each of which is linked by land lines or microwave relays to the appropriate domestic communication systems.

The repeater consists of a transistorized UHF receiver and an L-band (2 KMC) transmitter having a power output of 2.5 watts. Since the electrical power is supplied by solar cells, the useful life of the repeater is expected to be limited only by the life of the transmitting tube to about one year. Besides serving as the communication repeater, the receiver-transmitter is also used as a guidance signal repeater, and the receiver additionally acts as a command receiver.

The payload also contains a compressed nitrogen attitude and vernier velocity control system, which provides for proper illumination of the solar cells, correct aiming of the directional antenna, and precise adjustments of the orbit.

The ground terminals consist of a large aperture antenna shared by the 25-KW [kilo- watt] UHF transmitter and the low noise L-band receiver. The antenna reflector will be fixed, and the small departures of the payload from an exactly stationary orbit will be fol- lowed by moving the antenna feed.

The satellite is launched using the NASA Scout, and two additional solid-propellant rockets are used to establish the desired orbit. The launching site will be Jarvis Island, an equatorial island approximately 1300 nautical miles south of Hawaii. The use of this suit- ably located equatorial site results in a large decrease in required propulsion system per- formance and guidance complexity.

Further technical detail is furnished by the following sections of this proposal.  (omitted from the NASA publication)

6. PROGRAM COST

An estimate of the development cost of the communication system is given in Table 6-1, and an estimate of the cost of the entire program is given in Table 6-2.

The amount of confidence which can be placed in these figures is worth some discussion. The costs of the Scout rocket, attitude guidance, launcher, and ground support equipment were obtained from the Vought Astronautics brochure, “Space Research Vehicle Systems Developed from NASA Scout,” published in August, 1959. The UHF TV transmitter is a production item and its cost is firm. The cost of the ground antenna was estimated by an experienced supplier of such devices. Island construction costs were estimated by an overseas construction company which has had considerable experience with [Atomic Energy Commission] projects in the Marshall Islands.

The development cost estimates were obtained from the individuals who would be responsible for the various items. Although some variation in cost of particular items is to be expected, the chances that the total will remain under the 1.2 million dollar figure seems quite good, because of the strong appeal of the project to creative engineers and the subsequent high degree of enthusiasm with which the job will be performed

Table 6.1 Development Cost

Payload
     TWT $0.15M
     Structure   0.15M
     5th and 6th Stages   0.05M
     Environmental Testing   0.25M
          Total $0.70M
Terminal
     Antenna Design $0.05M
     Transmitter Modifications   0.05M
     Low Noise Receiver Design   0.10M
          Total $0.20M
Guidance-Perigee
     Transmitter Design $0.05M
     Receiver Design   0.09M
     Antennas   0.02M
     Computer   0.04M
          Total $0.20M
Guidance-Apogee
     Auxiliary Antennas $0.05M
     Computer   0.05M
          Total $0.10M
Total Development Cost $1.20M

 

Table 6.2 Program Cost

Development Cost
Terminal Cost
     Antenna $0.30M
     Transmitter   0.12M
     Receiver   0.03M
     Building and Land   0.10M
$0.55M     X 2      $1.10M (2)
Jarvis Island Construction
     Construction of Buildings $0.25M
     Construction of Airstrips   0.25M
     Launcher   0.25M
     Ground Support Equipment   0.70M
     Transportation   0.25M
$1.70M     X 2      $3.40M (2)
Launchings
     Scout with Attitude Guidance $0.361M
     Payload   0.072M
$0.433M   X 3      $1.30M (3)
Miscellaneous
     Salaries of Field Personnel $0.200M
     Reserve   0.200M
$0.400M      $0.40M
Total Program Cost      $5.00M

7. CONCLUSIONS AND RECOMMENDATIONS

It is concluded that it is technically feasible, within the present state of the art of rocket and electronic technology, to establish a commercial 24-hour communication satellite using the Scout rocket vehicle. It is recommended that NASA encourage such a program and recognize it as an important new application of the Scout. This program can be accomplished by the Hughes Aircraft Company within a year at a cost of 5 million dollars.

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