LMDS: A Fixed-Wireless Opportunity for Colleges and Universities




Educom Review table of contents
September/October 1999
This article was published in Educom Review, Volume 34 Number 5 1999. The copyright is by EDUCAUSE. See http://www.educause.edu/copyright.html for additional copyright information.
An EDUCAUSE publication



LMDS: A Fixed-Wireless Opportunity for Colleges and Universities

Recent spectrum auctions by the Federal Communications Commission (FCC) promise to enable a cost-effective last-mile broadband opportunity for many colleges and universities. Although it has some limitations, Local Multipoint Distribution Service (LMDS) could be a good solution for high-speed connections on campus -- without the cost of laying or upgrading wireline infrastructure. Getting from here to there, however, will require some technological homework and a willingness to bear the tradeoff of being an early adopter.

The Technology

LMDS is a fixed-wireless last-mile access technology, competing with both local telephone companies and cable providers. A very flexible, two-way broadband pipeline, it can be used for both point-to-point and point-to-multipoint communication within its somewhat limited range. Unlike most conventional radio (which uses high power and a low frequency and can travel long distances), LMDS is a low-power microwave technology with a high frequency that can travel only a short distance -- usually limited to a cell radius of about 10 kilometers.

With the high frequency of LMDS comes a very short wavelength; it cannot bend around obstacles. Accordingly, a clear line-of-sight is essential between an LMDS transmission site and the receiving building. Heavy rain is also a concern, but "rain fade" can be alleviated by simply upping the power. Some systems in development utilize a dynamic power-increase capability, which senses rain and adjusts the system power appropriately.

Although line-of-sight is a major constraint, LMDS nevertheless has great potential for a campus environment because of its huge capacity, particularly if the campus is relatively compact (e.g., within a 10-km radius). Most estimates place the typical LMDS throughput somewhere in the neighborhood of 1 - 1.5 gigabits per second, an order of magnitude greater than the current last-mile broadband offerings of the telephone companies (DSL: 256 Kbps - 1.5 Mbps) and the cable providers (cable modems: 500 Kbps - 2 Mbps). Compared with the cost of laying fiber or upgrading a copper plant, the cost of installing LMDS can be much less, making LMDS very cost-effective as a high-bandwidth link between a LAN and a WAN point-of-presence. Economies of scale suggest this to be particularly true for buildings that have high-demand LAN or that house a high concentration of users (such as dormitories).

Regarding applications, bandwidth licensed in the LMDS spectrum auctions is sufficient to broadcast all the channels of direct-broadcast satellite TV, all of the local broadcast channels, and up to 1 gigabit of full-duplex data service in addition to voice telephony. FCC literature states, "Because of its multi-purpose applications, LMDS has the potential to become a major competitor to local exchange and cable television services." LMDS is touted by some as a viable method for bypassing the local exchange carrier.

The LMDS Spectrum Auctions

In 1998 and early 1999, the FCC in two separate auctions sold off two blocks of spectrum for each of the 493 geographic Basic Trading Areas (BTAs), for a total of 986 licenses. The larger "A" block is 1.15 GHz wide. The "B" block licenses are a narrower 150 MHz.

The first auction in 1998 netted considerably less than expected, and over 100 rural BTAs never received a bid. The FCC was forced to hold a re-auction in early 1999, at which it sold all of the remaining licenses. Accordingly, to implement an LMDS solution in your area, you will need to contact the license-holder(s). To identify the LMDS license-holder in your area, visit the auction section of the FCC Web site (http://www.fcc.gov/wtb/auction/), which includes downloadable Excel files of the successful bidders in each BTA for each of the two LMDS auctions.

The FCC did a couple of interesting things for these auctions. First, local cable companies and incumbent local exchange carriers are prohibited from acquiring A-block LMDS licenses in their markets for three years, reflecting a desire by the FCC to promote facilities-based competition. Second, ten years from now, license-holders will be required to submit evidence of "substantial service" within their LMDS market or else risk forfeiture of their license.

The Virginia Tech LMDS Test-bed

Virginia Tech is engaged in the nation's first partnership between a university and the private sector for the deployment of a point-to-multipoint LMDS network. Before the first LMDS auction in 1998, Virginia Tech correctly anticipated that only high-population urban markets would be of interest to the bidding companies; over 100 rural markets across the United States, including the region surrounding Blacksburg and Virginia Tech, attracted no commercial bidders. "Virginia Tech's participation in the auction was predicated on the assumption that this technology will not be developed in rural areas due to the expense of build-out coupled with relatively low profit potential." (See "Virginia Tech LMDS Overview," available at: http://www.lmds.vt.edu/Main/ lmds_brochure.htm.)

In early 1998, Virginia Tech became the first university in the nation to participate in an FCC spectrum auction and was awarded four LMDS licenses covering 16,507 square miles in Virginia, North Carolina, and Tennessee. The region has an estimated population of 1.6 million. The university will use the spectrum to establish a research test-bed for advanced wireless communications, with particular emphasis on rural regions of the country. It also hopes to use LMDS to remove the bottleneck to Net.Work.Virginia and other advanced networks.

Virginia Tech's LMDS test-bed project is interdisciplinary, involving university geographers, economists, business and marketing faculty, electrical engineers, and computer scientists. A Washington-based company called Wavtrace is supplying the technology. For more information on the Virginia Tech project, see its Web site: http://www.lmds.vt.edu/.


LMDS is promising but is in the early stages of development. As with any new technology, the first few generations of equipment will be expensive. Higher education institutions that seek to take advantage of the fixed-wireless opportunities should be prepared for the tradeoff and trial-and-error difficulties of being an early adopter. Conversely, being an early adopter has some intrinsic value beyond the benefits of the technology itself. New technologies need test-beds. Vendors and license-holders are quite likely to be receptive to creative partnerships with universities. In addition, LMDS implementation can be an excellent network research or educational opportunity for university faculty or graduate students.

Rural institutions may find that the lack of commercial viability for LMDS deployment in their areas works to their benefit. Leasing arrangements or outright license purchase could be cost-effective. As anchor tenants, university campuses can play a decisive role in enabling a broadband last-mile wireless infrastructure in the area.

  1. As noted above, all of the LMDS licenses have been auctioned off. Virginia Tech is apparently the only university to have obtained licenses, so a direct replication of the Virginia Tech model may be extraordinary. Nevertheless, we encourage campuses to understand the circumstances of their local market and to analyze opportunities, perhaps initiating contact with local LMDS license-holders. Virginia Tech suggests that the following steps be taken by communities that want to explore LMDS. The advice is equally good for universities:
  2. Identify local advocates. Ideally, set up a steering committee of local businesspeople, educators, health workers, and other interested citizens.
  3. Generate government and political support through the education of local decision-makers. Advise council members, town-city managers, and others to create ordinances and policies that will facilitate the establishment of a healthy network infrastructure.
  4. Develop viable business and technical plans. Examine the market to determine the mix of access solutions and services that would best be utilized by the population.
  5. Identify potential funding sources and partners. Be prepared to work with municipalities, businesses, and other interested partners to purchase and implement LMDS technology in your region.


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