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Loma Scientific International - MMDS Transmitters, Microwave Power Amplifiers and Broadcast Television Systems

A Broadband Wireless Access MMDS Transmitter Manufacturer and Systems Company

1. What is some of the history of Wireless Cable?
        In 1970, the FCC authorized a new service known as MDS (Multipoint Distribution Service) that was intended for transmission of business data. Being very similar to ITFS technology, it was an obvious product evolution.

S-band Spectrum Allocations

Over the next decade the need for additional spectrum convinced the FCC to develop a channel usage plan to include both ITFS & MDS interests. In 1984, the FCC authorized the use of educational programming frequencies for pay television service, which became known as Wireless Cable or Multichannel MDS. Eight years later in 1992 Congress revised the Cable Act that eliminated the monopolized pricing held by traditional hard-wired cable operators. This was a major breakthrough for the wireless cable industry. Now, the wireless cable operator could offer what consumers demanded. This sparked the growth of the wireless cable industry.
        Growth in wireless cable was the result of simple economics: cash flow and profitability. It is less expensive and more cost-efficient to install antennas and downconverters than it is to bury cable, maintain cable, and replace coax with fiber. The investment in wireless is in subscriber equipment, not network, thus making the investment proportional to the number of subscribers; also these costs are only incurred when an installation is made and one has a paying customer. This holds true for urban as well as suburban and rural installations. MMDS is no longer the "Poor man's cable," which it was once referred. It is a leader in today's convergence of video, data, and voice; a single technology capable of providing digital television, high speed 2-way wireless Internet access and data networking, and even local telephone service.

2. What is Sprint and WorldCom doing?
        In March 1999, Sprint and WorldCom began acquiring selected MMDS license holders. They have begun plans to use the MMDS spectrum to launch wireless high-speed Internet services. These services will compete with cable, fiber and DSL to provide high-speed connectivity options nationwide. Sprint, WorldCom, BellSouth and Neucentrix collectively hold approximately 90% of the US MMDS licenses. Additionally, various operators worldwide are currently conducting similar trials of wireless Internet services. Only time will tell the extent and success of the ongoing propagation of MMDS based services and its convergence into the mainstream.

3. What does a two-way data transceiver (transverter) do?
        A typical transceiver provides the wireless interface for cable modems at the subscriber's site. It provides the corresponding inverse frequency conversion functions of the headend's downstream transmitter and upstream receiver equipment. I.e. a transceiver includes a low noise downstream receiver and a frequency stable upstream transmitter. In fact, if the two data streams employ the same modulation and bandwidths, then the transceiver can be considered full duplex. Also, in point-to-point applications or for a small numbers of subscriber terminals, it is possible to use the same high power transceiver for headend and subscriber RF interfaces by simply switching the high/low ports of the transceiver's antenna duplexer exclusively, for example, on the headend unit.

4. What are DVB and MPE?
        DVB stands for Digital Video Broadcasting. It is the European digital TV standard, with three main variants: DVB-C for Cable TV, DVB-S for Satellite TV and DVB-T for Terrestrial TV. DVB is an open standard. MPE stands for Multi-Protocol Encapsulation, the way in which IP addresses are mapped to MAC (Media Access Control) addresses. MAC addresses are hardware specific.

5. What kind of services can IP over Broadband provide?
        Broadband Internet provides a much faster Internet experience for the end-user, utilizing high-speed infrastructure such as cable TV, satellite or digital terrestrial TV. The services users receive include: web surfing, software downloading (FTP), e-mail, high speed games and virtual reality worlds, distance learning applications, high-quality streaming of audio, video, and data, multicasting (Best of Web, Web events etc.) as well as additional capabilities such as e-commerce.


Loma Scientific International
3115 Kashiwa Street, Torrance, CA 90505 USA
Telephone: (310) 539-8655, FAX:  (310) 539-8634, e-mail: info@lomasci.com

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