Globalstar
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Globalstar is a low Earth orbit (LEO) satellite constellation for satellite phone and low-speed data communications, somewhat similar to the Iridium and Orbcomm satellite systems.
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[edit] Telecommunications system
[edit] System architecture
- Globalstar satellites are simple "bent pipe" repeaters. A network of ground gateway stations provides connectivity from the 40 satellites to the public switched telephone network; users are assigned telephone numbers on the North American Numbering Plan in North America or the appropriate telephone numbering plan for the country that the overseas gateway is located in, except for Brazil, where the official Globalstar country code (+8818) is used. Because there is no inter-satellite linking, a satellite must have a gateway station in view to provide service to any users it may see. Because there are no gateway stations to cover certain remote areas (such as oceans areas far from land), no service can be provided in those areas even though the satellites fly over them.
- Globalstar orbits have an inclination of 52 degrees therefore Globalstar does not cover polar areas due to the lower orbital inclination.
- Globalstar orbits have an orbital height of approximately 1400km and latency is still relatively low (approximately 60ms).
- A Globalstar bird has two body-mounted, Earth-facing arrays. First-generation Globalstars weight approximately 550 kg, However the second-generation Globalstar design will gain significant mass.
- The Globalstar system uses the Qualcomm CDMA air interface; however, the Ericsson and Telit phones accept standard GSM SIM cards, while the Qualcomm GSP-1600/1700 phones do not have a SIM card interface, but use CDMA/IS-41 based authentication. Therefore the Globalstar gateways need to support both the CDMA/IS-41 and the GSM standards, which not all gateways do. This results in the lack of coverage for GSM authentication based phones in the Eastern Asian and Caribbean region, as stated on the coverage map: [1]
Most Globalstar providers have roaming agreements with local cellular operators, enabling the use of a cellular SIM card with a Globalstar handset and vice versa.
[edit] System deployment
Globalstar received its U.S. spectrum allocation from the FCC in January 1995, and continued to negotiate with various other sovereign nations for rights to use the same radio frequencies in their countries.
The first satellites were launched in February 1998, but system deployment was delayed through a series of embarrassing and costly launch failures, notably the September 1998 loss of 12 satellites in a launch by the Russian Space Agency. In February 2000, it launched the last of 52 satellites: 48 satellites and four spares (reduced from the original plan of eight spares).
The first call on the Globalstar system was placed on November 1, 1998, from Irwin Jacobs (chairman of Qualcomm) in San Diego to Bernard Schwartz (CEO and chairman of Loral Space and Communications) in New York.
In October 1999, the system began "friendly user" trials with 44 of 48 planned satellites. In December 1999, the system began limited commercial service (200 users) with the full 48 satellites (no spares in orbit). In February 2000, it began full commercial service with its 48 satellites and 4 spares in North America, Europe and Brazil. Initial prices were $1.79/minute.
In 2005, some of the satellites began to reach the limit of their operational lifetime of 7.5 years. In December of 2005, Globalstar began to move some of its satellites into a graveyard orbit above LEO. [2]
[edit] Recent problems
According to documents filed with the SEC on January 30, 2007, Globalstar's previously identified problems with its S-band amplifiers used on its satellites for two-way communications are occurring at a rate faster than previously believed, possibly eventually leading to total loss of service in 2008.
In the filing, Globalstar made the following statements:
"Based on data recently collected from satellite operations, the Company has concluded that the degradation of the amplifiers is now occurring at a rate that is faster than previously experienced and faster than the Company had previously anticipated."
"Based on its most recent analysis, the Company now believes that, if the degradation of the S-band antenna amplifiers continues at the current rate or further accelerates, and if the Company is unsuccessful in developing additional technical solutions, the quality of two-way communications services will decline, and by some time in 2008 substantially all of the Company’s currently in-orbit satellites will cease to be able to support two-way communications services." [3]
Industry analysts speculate the problem is caused by radiation exposure the satellites receive when they pass through the South Atlantic Anomaly in their 876 mile (1414 km) altitude orbits.[1]
"The S-band antenna amplifier degradation does not affect adversely the Company’s one-way “Simplex” data transmission services, which utilize only the L-band uplink from a subscriber’s “Simplex” terminal to the satellites. " [4]
"The Company is working on plans, including new products and services and pricing programs, and exploring the feasibility of accelerating procurement and launch of its second-generation satellite constellation, to attempt to reduce the effects of this problem upon its customers and operations. The Company will be able to forecast the duration of service coverage at any particular location in its service area and intends to make this information available without charge to its service providers, including its wholly owned operating subsidiaries, so that they may work with their subscribers to reduce the impact of the degradation in service quality in their respective service areas. The Company is also reviewing its business plan in light of these developments. " [5]
"The Company’s liquidity remains strong. At December 31, 2006, in addition to its credit agreement, the Company had unrestricted cash on hand and undrawn amounts under the Thermo Funding Company irrevocable standby stock purchase agreement of approximately $195 million." [6]
[edit] Globalstar's Interim Solution
On 18 April 2007 Globalstar announced they would launch eight spare satellites to augment the company’s existing first-generation LEO satellite constellation.[2] On 29 May 2007 the first four of these satellites were launched by Starsem from the Baikonur Cosmodrome in Kazakhstan atop a Soyuz-FG/Fregat rocket. The second launch, also aboard a Soyuz-FG/Fregat from Baikonur, was launched on 2007-10-20.[3]
However, it is still not clear when the new satellites will improve phone communications. The Globalstar website is mute on this issue. Most current users in summer 2007 report difficulty using the phones, with very short communication windows of 1–2 minutes and frequently dropped calls[citation needed]. In addition, an offshore fishing magazine (Big Game Fishing Journal) wrote an editorial in their July 2007 issue on the poor service of Globalstar [7].
[edit] Globalstar's Second-Generation
In December 2006, Globalstar announced that Alcatel Alenia Space, now Thales Alenia Space, has been awarded a EUR 661 million contract for the second-generation 48 satellite constellation. [8]
The satellites are being designed with a life expectancy of 15 years, which is significantly longer than the design life of Globalstar’s first generation constellation.
In addition, Globalstar announced on April, 03, 2007 that it has signed a EUR 9 million (approximately US$ 12 million) agreement with Alcatel Alenia Space to upgrade the Globalstar satellite constellation, including necessary hardware and software upgrades to Globalstar’s satellite control network facilities. [9]
This second-generation of satellites are expected to provide service to Globalstar customers with satellite voice and data services until at least 2025.
[edit] Business operations
[edit] Corporate structure and financing
The Globalstar project was launched in 1991 as a joint venture of Loral Corp. and Qualcomm. On March 24, 1994, the two sponsors announced formation of Globalstar L.P. (a limited partnership incorporated in the U.S.) with financial participation from eight other companies, including Alcatel, AirTouch, Deutsche Aerospace, Hyundai and Vodafone. At that time, the company predicted the system would launch in 1998 based on an investment of $1.8 billion.
In February 1995, Globalstar Telecommunications Ltd. raised $200 million from its initial public offering in the NASDAQ market. The IPO price of $20 per share was equivalent to $5 per share after two stock splits. The stock price peaked at (post split) $50 per share in January 2000, but institutional investors began predicting bankruptcy as early as June 2000. The stock price eventually fell below $1 per share, and the stock was delisted by NASDAQ in June 2001.
After the IPO, the publicly traded Globalstar Telecommunications (NASDAQ symbol GSTRF) owned part of system operator Globalstar LP. From that point on, the primary financing for Globastar LP was vendor financing from its suppliers (including Loral and Qualcomm), supplemented by junk bonds.
After a total debt and equity investment of $4.3 billion, on February 15, 2002 Globalstar Telecommunications filed for Chapter 11 bankruptcy, listing assets of $570 million and liabilities of $3.3 billion. The assets were later bought for $43 million by Thermo Capital Partners LLC. When the new Globalstar emerged from bankruptcy in April 2004, it was owned by Thermo Capital Partners (81.25%) and the original creditors of Globalstar L.P. (18.75%).
[edit] SPOT Inc.
In August 2007, Globalstar announced the introduction of the "SPOT Satellite Messenger" product, to be marketed through its latest subsidiary SPOT Inc. [10] The SPOT Messenger is manufactured by Globalstar partner Axonn LLC [11] and combines the company's simplex data technology with a Nemerix GPS chipset. SPOT is intended to leverage Globalstar's still adequate L-Band uplink, which is used by simplex modems. The product was launched early November 2007.
[edit] Employees
The first five employees of Globalstar were transferred from the founding companies in 1991. Although few figures were publicly disclosed, the company apparently reached a peak of about 350 employees until layoffs in March 2001. However, this figure was misleading as most of the development, operations and sales employees were employed by the company’s strategic partners.
Loral’s chairman Bernard Schwartz served as Globalstar’s chairman and CEO until May 2001.
The company then appointed satellite telecommunications veteran Olof Lundberg to lead a turnaround at the company to serve as chairman and CEO. After beginning his career with Swedish Telecom, Lundberg had been founding Director General (later CEO) of Inmarsat from 1979–1995. He served as founding CEO and later CEO and Chairman ICO Global Communications from 1995–1999.
Lundberg resigned from the company (then in bankruptcy) as of June 30, 2003.
[edit] References
- ^ Space Intelligence News. Ascend (March, 2007).
- ^ Globalstar’s Soyuz #7 Launch Campaign is Underway in Baikonur. Globalstar.
- ^ Four Globalstar satellites put into orbit by Russian rocket. AFP.
[edit] Bibliography
- (French)(English) Guy Lebègue, (trad. Robert J. Amral), « Globalstar Mobile Telephony: Planetwide within three Years », in Revue aerospatiale, n°115, February 1995.
