Satellite Communication Components for Communication Satellites Part III

The simple basic application of any communication satellite, whether it is low earth orbital or geosynchronous, involves transmission of information from an originating Earth station to the satellite concerned, which is termed as “up-linking,” followed by re-transmission of the same information to the designated Earth station. This re-transmission is termed as “down-linking.” The downlink of the information may be to one particular Earth station or broadcasted over a selected number of Earth stations, situated at a larger area. In order to perform this up-linking and down-linking, the satellite has a receiver and a receive antenna, a transmitter and a transmit antenna, just like a set of walkie-talkie, which has a receiver and a transmitter with an antenna, though, in here, the “receive” and “transmit” are done through the same antenna. Satellites need antennas separately for its two functions of receive and transmit. Additionally, the satellite has electronic switches. This is used to logically switch the uplink signals, down-linking it to the appropriate Earth stations. It has an electronic black-box to determine the destination or destinations of the signals being down-linked to the Earth Stations. There is that ever important electrical power in a satellite required in keeping alive the electronic circuitry. The exact component structure of a satellite may differ from one to the other, depending on its actual application, but the basic component requirements remain the same.

The electrical power needed by satellites for receiving and transmitting signals greatly depend upon its orbital path, that is, whether it is a low Earth or geosynchronous orbital satellite. Electrical power requirement mostly depend upon the height of the satellite above the Earth. The higher it is, a satellite would need that much power for its basic operation in receiving and transmitting signals On basis of this, a geosynchronous satellite, being at an altitude of 22,300 miles, would require much more electrical power than the low earth orbiting satellite, which is situated at only a few hundred miles from Earth. In theory, a geosynchronous satellite would need 10,000 times the electrical power than the low Earth orbiting satellite. This is an awful lot of power and the satellite is designed in a way to work out a compromise, without losing the application reliability.

A satellite is usually powered from a battery or a solar energy system. In some of the communication satellites, a combination of battery and solar power energy is used, with the batteries supplying power to the electronics circuitry in the satellite, with a change over to solar energy during sunlight cycle, when the batteries are left on charging. The battery is turned on during solar eclipses, when the solar panels become inactive.

The main difference between the satellites in different orbital path is the antenna. This antenna design sets the optimum power requirement of a satellite. There are basically many designs available for an antenna. Some direct their radiation to one particular direction and there are others which are omni-directional, radiating all around. This principle is carried further by a communication satellite. If you consider the height at which the satellite is orbiting, even a large area on this Earth will be a mere spot of an area from that height. With the earth stations located in a comparatively small area, a properly designed antenna will beam its signals within that constricted area and not in any other direction. With a bigger antenna dish diameter, the area of radiation decreases in relation to certain design parameters.

Approvals For Setting Up an Indian Satellite System and Provision of Satellite Service in India

Approvals, Registrations and Authorizations Required for Setting up an Indian Satellite System and Provision of Satellite Services by Satellite Operators in India

In my previous articles on provision of satellite services in India, we analyzed the regulatory framework and the possible entry options available to foreign satellite operators to establish its business presence in India and provide satellite services in the Indian subcontinent. One of the entry option is setting up an Indian Satellite System (“ISS”) by the foreign satellite operator for providing satellite based services on a commercial basis in India and be eligible for all the preferential treatment accorded to such systems in service provisioning in India. For the purposes of establishing an ISS, the foreign satellite operator and/or domestic Indian company, as the case may be, (“Satellite Company”) would need to obtain various approvals and registrations with the Indian regulatory authorities.

Incorporation of the Indian Company

For the purposes of setting up of an ISS, Satellite Company would need to incorporate a company (“Newco”) under Indian laws. Under the Companies Act, 1956 of India, a company limited by shares may be incorporated either as a private company or as a public company. Under tax and other statutes and regulations, private and public companies are ordinarily treated similarly. Therefore, Satellite Company may consider incorporating Newco as a private company.

Registration with CAISS

In the year 1997-1998, the Government of India (“GoI”) announced the Satellite Communication Policy Framework (“SatCom Policy”) and formulated the norms, guidelines, and procedure for registration of Indian satellite systems by private Indian companies and allowed limited use of foreign satellites (i.e., uplink from India) in special circumstances provided the satellites were coordinated with the INSAT satellites. Pursuant to the SatCom Policy, the GoI authorized Indian Space Research Organization (“ISRO”) to set up a Committee for Authorizing the establishment and operation of Indian Satellite Systems (“CAISS”), with its Secretariat at the Satellite Communication Programs Office at ISRO Headquarters at Bangalore.

For the purposes of registration with CAISS, Newco would need to submit a detailed project proposal to CAISS stating details of its project including the aims, objectives and background of Newco including its equity structure; the satellite proposed to be launched or leased, spacecraft description, manufacturing and launch details of the satellite, capabilities of all payloads and system, network description and characteristics, orbit spectrum requirements, spacecraft launch vehicle; data and location of satellite launches proposed by Newco, etc.

The Satellite Coordination Programme Office, which serves as the Secretariat of CAISS, reviews and examines the application in light of the SatCom Policy and the norms and guidelines and procedures approved by the GoI. The Secretariat will, thereafter, put up the application for CAISS’ consideration.

Satellite Phone Rentals

Some of the satellite phones are bigger in size than the mobile phones that you see today and heavier too. It is more expensive to buy compared to your mobile handset. In the event you find yourself in a situation where you require the guarantee of connectivity, where the other alternatives do not exist or are scarce, a satellite phone becomes an invaluable means to meet your general communication requirements and possibly a life saver as well. In such cases you may consider renting a satellite phone, which is affordable and becomes a valuable and essential asset in your journey to the middle of no-where.

A satellite phone needs the open sky to operate. It cannot be used from inside a building or in such places where the sky is not visible. It is the antenna of a satellite phone which should have the sight of the clear sky above, for the phone to operate. This would mean that such phones will not work indoors unless you are by the side of a window with a view of the clear sky. Not only that, the window should face such a direction where the concerned satellite currently is, if the satellite happens to be a Low Earth Orbiting (LEO) satellite. There is the other type, which is called a Geostationary Earth Orbiting (GEO) satellite, remains in the steady state relative to the Earth’s movement. While LEO satellite orbits the Earth at a relatively low altitude, a few hundred miles above the Earth, GEO satellites are placed at about 22,000 to 32,000 miles above the Earth, where they remain in the same position above the Earth’s surface at all the time.

If you are on a ship, you might have to go on to the deck to be sure to have that open space for a reliable operation of your satellite phone. If you are in a car, you would put that external antenna that came along with your phone on the roof of the car to have a reliable connectivity. But mind you, you may have difficulties of dropped calls in urban areas because of the high rise buildings. If you are outside but in the middle of a forest, the trees might block the line of sight of the satellite and your calls may get dropped or disrupted.

The GEO satellites, being placed much higher than the LEOs, cover a greater part of the earth, are able to see a larger area. On the other hand, the LEOs would need a constellation of satellites to relay the communication information from one satellite to the other, for it to reach the desired destination. The LEO satellite orbits the Earth once in about 90 to 100 minutes and this is the reason why the round-trip time for transmission is minimal. More-over, being at a lower altitude, some 600 miles above the Earth, the power required to transmit signals from Earth is much lower compared to the GEO satellites. Satellite phones, serviced by LEO satellites, require a shorter antenna, while the ones meant for the GEOs are quite larger in order to accommodate for the power required to transmit signals to the concerned satellite. The disadvantage of LEO satellites is that they need to operate in a fleet as they orbit the Earth at a larger speed, synchronised in the manner that when one satellite moves out of a certain position, the next one takes over.

Satellite Communication Overview of the Technology & the Antenna System Part IV

Key Issues

Looking ahead of 1990’s, one could observe a very rapid expansion of global market in satellite communication into personal communication and new mobile satellite services, such as Personal Communication System (PCS) and Mobile satellite Services (MSS) respectively, Low Earth Orbit (LEO) satellite systems, Global Positioning System (GPS) navigation, and new direct broadcast satellite services. LEO satellite services were introduced towards the end of 1990’s, and the growth depended on the competitive factors. The conventional Fixed Satellite services (FSS) and Maritime Mobile Satellite Services (MMSS) grew steadily but not as before.

Optical fiber cables, now forming a greater part of this communication revolution through out the world, severely challenged the fixed satellite services. Very high data rates, similar to High Dynamic Range (HDR) graphics, which requires greater than 155Mb per second of data transfer, which required excellent signal conditioning, were being carried by the fiber optics cables. Fiber optic cables have a better performance than satellites, having much less time delay in transmission. It was a time when satellite services needed to prove its advantage on HDR applications and networking, having a more modest data rates, for example T1=1.5Mb per second. A T-1 line actually consists of 24 individual channels, each of which supports up-to 64Kbits per second data rate. The advantages include, wide area coverage, distance insensitivity, flexibility, multiple access and destination capabilities and economy. Although much of the HDR traffic, such as multi-channel telephone trunks, from satellites to cables, will be transmitted through fiber optics cables, new opportunities opened up for HDR satellites to carry HDTV picture signal distribution, and also support the emerging field of Distributed High Performance Computing (DHPC). To gain access to this application market, HDR satellites needed to be developed and deployed commercially.

It was clear by now that the world of satellite communication was changing fast and threats existed for fixed satellite services, while new opportunities opened up in mobile, broadcast and personal services. Presently, the US leadership in satellite communication is being challenged, while it was undoubtedly the leader of such technology and was an agent of the changes in the past.

There are reasons as to why there has been a bleak assessment of the future of US in satellite communication technology. The important reasons include, the governments reduced role, lagging R&D effort, lack of systems conceptualisation, non-focusing of effort in new applications, and lack of effective industrial liaison and co-operation. On record, the assessment shows that during 1970’s and 1980’s there was extremely limited activity in US in the area of satellite communications projects, while there were frequent diverse research programs that were going on in Europe and Japan. Although these projects are of a different technology and much less budgeted than the US ones, the overall impression of US losing ground in the area of satellite communication is essentially correct.

The setting up of policy, planning, and supporting industrial development in different countries varies widely, with the governments of each country playing a key role in such activities. The policies and planning of the governments in Europe and Japan are far more aggressive than that of US, with the resources for such development being far more deployed. In-fact, in the last ten years, NASA has spent much less in satellite communication than its counterparts, the Japanese National Space Development Agency (NASDA) or the European Space Agency (ESA), although NASA’s total budget is many times greater.

Satellite Phone Sales

Geostationary satellite phones versus civilian use satellite phones

Although satellite telephones can be used for geostationary orbit connecting the whole world with only three or four satellites, the most popular civilian system is Inmarsat. Geostationary satellite phone requires a large antenna system for signal receipt and transmission. This makes the entire system inconveniently large and affects mobility and ease of use, quite adversely. Civilian satellite phones such Inmarsat, is quite handy to use and does not require such a large system of antenna. However, every satellite hand held phone system suffers from a big disadvantage that they need a clear link with the sky and are unusable inside a building. Here the requirement will be that of external antenna and it makes the whole process quite cumbersome and costly too.

Satellite phones using Low Earth Orbit technology

These satellite phones have the rare advantage of covering the world without wire and without any gaps. Low Earth Orbit satellites go round the earth at a very high speed but at lower altitude with an orbital time of around 90 minutes. The altitude at which these satellites move are somewhere between 600 to 1,150 Kms. The original two LEO systems are Iridium and Gobalstar could not become popular.

Satellite phones models

Satellite phones have been quite popular in films and stage shows. They are available in various models and come from divergent brands. The most popular ones are Globalstar, Iridium, and Inmarsat. A prospective user need not always purchase one since satellite phones on rental are also available. Satellite phones can also be purchased by ordering online. Most of the providers also have the system of same day delivery or door delivery, as preferred by the customers. In addition they offer attractive plans to gain customer support like no deposits, an extra free battery, and unlimited use with no bundled minutes, fastest shipping, and many more. An example is the International Cell Phone rental package offered by some, that provides connectivity to 130 countries with pulse rate payment ranging from 89 cents to $1.69.

Transition from commercial to consumer use

At the start of the millennium, satellite phones were yet to make a big headway and most of the providers were struggling for self-sufficiency. The most pertinent reason behind such a state of affairs was the high payable cost and high payable pulse rate. For example the Globalstar handheld phone cost around $1,200 and the pulse rate payable was $2.49 per minute. Inmarsat was also providing a bulky suitcase set at $3,000 to $10,000. Therefore, initially the users of satellite phones were the Government and big business houses. They used the satellite phone services to approach remote areas having none other means of communication. Even the rental charges in 2001 were an unfriendly $159 per week with call charges at $3.99 per minute. However, over the past five years there has been a sea change in this area. The first popular service of satellite phone system was provided by Iridum with a cost of $1,995 or the same was available on rent at $19.99 per month. The pulse rate payment was a reasonable $1.99 and these rates were much lower than earlier rates charged for satellite phones.

The initial steps in transition from commercial to consumer based satellite phones took place in 2001 with the launching of Iridium World Data Services. It provided for dial up throughput of 2.4 kbps and direct Internet data throughput at about 10 kbps. A package with a pulse rate payment of 99 cents per minute was also introduced. And the most important addition was the prepaid phone service at an average pulse rate of $1.09 per minute. The satellite phone service, originally opened for Government only, has now become open to the private customers. Today, providers like Globalstar has reduced the satellite phone costs by 80% of its cost in 2001.

The user scenario

However, the largest user till date of satellite phones is the Military. Today, Globalstar provides handheld satellite phone at $645, and sets are available at a lower price of $599. The 2006 Inmarsat has voice and high speed data service. But the cost is higher at $1,650, with the advantage that it provides for BGAN services not available till now. This technology eliminates the necessity to use terminals that earlier cost a customer nearly $8,000. The advantage of this technology is clear digital voice and high speed data transfer. Gradually, the popularity of satellite phones started increasing and the average revenue collection marked at 30% increase for the industries involved. With a 60% downfall in the rentals for satellite phones, the consumer strength has multiplied into virtual millions. The growing consciousness among prospective customers about the ease of transmission of data and voice through the satellite service has resulted in further growth of the satellite phones industry in the United States. The growth has been indicating an upward trend for last five years.