AccessTel (ATEL): 6.4 CDMA DEVELOPMENT (abbreviated from L...

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Sunday, 12/03/2000 2:36:57 AM

Sunday, December 03, 2000 2:36:57 AM

6.4 CDMA DEVELOPMENT (abbreviated from Lee's new book)

Quallcomm was a 200-employee company located in SD, CA. that was formed in 1985. Their main business at the beginning was Omnitrak, a system that tracked trucks. In Feb of '89, Q's 10 key people, led by Jacobs and Viterbi, visited Pactel (now Airtouch, now Vodaphone, now Verizon, lol). Gilhousen introduced the CDMA system for cellular use to them. they were talking about applying CDMA on the satellite communication to cellular. W. Lee from Pactel mentioned that the unique phenomenon to be considered in cellular was the near-mobile to far-mobile interference, or simply near-far interference. To apply CDMA, the cellular near-far interference problem should be resolved by using the power control scheme in CDMA. The power control schemes for FDMA or TDMA were much easier, and for CDMA it wasn't an easy or obvious task in 1989. CDMA had to control the power of each code sequence within a radio channel. Lee had studied the spread-spectrum system and was granted two patents in spread-specturum communications before 1985. He realized the difficulty of finding a power control scheme for cellular CDMA.
In April of '89, Q personnel visited Pactel again. They found a solution to power control in CDMA coded channels. After its successful power control presentation, Q asked for a $200k study contract from Pactel. At that time at Pactel, Lee, a corporate tech VP, suggested to Hultman, a cellular CEO, and Farrell, a network VP, that Q's paper study would be useless to Pactel. Pactel said it might support Qualcomm by giving it $1M if Q was willing to deliver a demonstration of CDMA in 6 months. Q accepted. The reason for finishing a CDMA demo in 6 months was that the American digital system (TDMA) was already voted as the digital system standard and in the stageof writing its specification. A symposium on digital standards was held and the next generation cellular technologies section was chaired by W. Lee. getting CDMA out to the public in a timely manner was very important. theoretically, CDMA proved that its capacity was at least 10 times that of AMPS. Such a system was what the ARTS of CTIA was looking for.
Hultman asked Lee to technically assist Q's demonstration and to be at Q at least once a week. Hultman and Farrill were handling other demonstration issues, ssuch as clearing Pactel's frequencies in the Pactel's SD mkt for a CDMA demonstration. Two Pactel cell sites plus Q's headquarter site were used for the demonstration.
the CDMA demonstration was a miracle.... (goes into a tech description) Q's engineers worked day and night. It was nto surprising to call Q's lab at midnight and find Whitley, Weaver, and Padovani and their people still there....
In Sept. '89, Q asked for another million to get the demonstration finished in Nov of '89. Hultman was a little concerned and asked Lee for his opinion during the joint meeting with Q. Lee answered Hultman's question with a Yes. Q was very happy, not only for the $1m, but also the strong support from a large operator which could be worth more.
On Nov 3 '89, the demonstration took place at Q headquarters in Serrendo valley. About 60 attendees camee, including domestic European, Korean, and Japanese companies. The demo was successfully completed. Lee's views of CDMA were printed on the first page of a flier (distributed during the demo) and a video tape as made during the demonstration. It was a shock to the cellular industry, but Q's demonstration gave the US cellular industry confidence and ensured that US companies had a strong capibility to push for technological excellency.
Q was not a cellular vendor company in '89, but Lee was known in the cellular industry, and he fully understood that CDMA had a greater capacity than TDMA. In Jan. '90, Lee took the initiative and gave a 1-day cellular CDMA seminar sponsered by the IEEE West Coast section... In March '90 Lee went to the East Coast to present the same seminar, sponsered by the IEEE NJ section and goodman's WIN Lab at Rutgers U. In May '90, Lee also talked about cellular CDMA at IEEE VTC'90 in NJ. On Dec. '90 Lee delivered a paper and participated in a workshop on CDMA at the IEEE GlobeCom Conference, SD, CA.
Lee's four presentations about the cellular CDMA system made a strong wave in the digital cellular community in early 1990. then, a special issue of IEEE, edited by Lee, was published in '91. There were three CDMA papers, Lee's overview of CDMA, Gelhousen's On the Capacity of a Cellular CDMA, and Pickholtz's Spread Spectrum for Mobile Communication.
In the past, each new system required at least 10 years of developmenmt before it was commercially viable...AMPS too nearly 20 years, GSM 10 years, TDMA 7 years, CMDA, however, took only 5 years, making its development the fastest in history.
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There is much more on Lee and Qualcomm's CDMA, especially Korea's development is interesting, it's all in the book, what's most obvious is that Q is much indebted to Lee:
http://www.investorshub.com/beta/read_msg.asp?message_id=22878

What's new is that Lee is moving into a new direction with China and AccessTel and LinkAir. You know, on a side point, it's kind of interesting thinking of these two in the relationship of PacTel and Qualcomm. Alot has been written about AccessTel, their recent CC transcript for reference:
http://www.investorshub.com/beta/read_msg.asp?message_id=24186

If you want to go into the realm of LinkAir and Lee's work with 3G wireless, this is some more of Lee's work, following a recent AccessTel info:
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In addition, AccessTel Inc.( recently RM'ed into OTCBB: SHPS) has completed the filing and registration with the appropriate authorities in China of their 100% owned subsidiary, AccessTel (China) INC. and has been approved by the Chinese Authorities for a term of operations of 20 years. AccessTel (China) INC. offices will be located in the CAOHEJING New Technology Development Zone, Shanghai.
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So their Chinese offices are going to be located in the premise of one of their first WLL contracts.

The big deal though is to move into what Lee calls a "Wireless Information Superhighway." To do this is going to take a "breakthrough technology." Here's is some of what I compiled about this technology before, roughly:
http://www.ragingbull.altavista.com/mboard/boards.cgi?board=SHPS&read=10447

From reading Lee, it becomes clearer that this is his aim, he's big on coding still, and thinks that "TDD is one of three 3G modes. In 4G, TDD will be the only mode. this is because TDD is a high-spectrum effiecient system."

"In wireless communications, the poor limitied bandwidth comes from the limitation of Mother Nature. Also, mobility causes another difficulty in persuing this high-speed data transmission requirement. To obtain a large bandwidth, the carrier frequencies must be up to millimeter wave links, we can apply the diversity scheme to increase the signal strength. Over the infrared links we can use diffuse transmissions to create multipaths and operate under out-of-sight conditions. Also, because the infrared can penetrate rainfall, but not fog, and the millimeter wave can penetrate fog, but not rainfall, we can create a dual-medium diversity reciever that uses both infrared and millimeter waves for the last 100-m wireless high-speed data link."

TDD and WLL work together nicely, as any international standard. Whatever system wins out, it'll have to be compatible with the different services (PCS, Cellular, WLL...) already out there. "The undesirable situation is numerous systems servicing the same service (CDMA, TDMA...)."
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In light of what Lee is saying and you look at what LinkAir is saying they have, and what AccessTel says they are doing with their WLL contract in Shanghai, things start to click:
http://www.investorshub.com/beta/read_msg.asp?message_id=25511

imo

imho, Jerome