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To: Bux who wrote (3740)	11/29/1999 3:05:00 AM
From: puzzlecraft	Read Replies (1) \| Respond to of 13582

Regarding Cisco V-OFDM and Wi-LAN W-OFDM: If the W-OFDM encoding were deployed in the PCS frequency, then the sustained rate would be 128Kbps, HDR would do a lot better at a sustained rate (and 1x and 3x technology will do well too); although the W-OFDM peak bursts would be faster, around 10Mbps according to Hatim. As a whole new W-OFDM mobile support infrastructure would have to be developed, years of testing and financing undertaken, and with no clear benefit for mobile it seems pretty pointless IMO to go ahead, as CDMA is already established, 1x and HDR well understood and well along to being first to market for higher mobile speeds. Wi-LAN's work with W-OFDM is for fixed communications, and mobile work would take a lot of $ to develop; Cisco's work with V-OFDM is also addressing the fixed area. For fixed point, W-OFDM has a good shot, but so does V-OFDM and from what I've read V-OFDM is much better at penetrating leaves and dealing with echos, etc., although it is not clear how much W-OFDM and V-OFDM IPR get in the way of each other. So far Cisco has not mentioned Wi-LAN in their announcement (as far as I know); W-LAN's announcements re: W-OFDM have been for indoor distribution / sharing of data from the network access point, although they have some work going on with outdoor fixed systems. IMO, IN THE VERY LONG RUN FIBER WILL CRUSH ALL WIRELESS FOR FIEXED HIGH SPEED ACCESS EXCEPT IN THE REMOTE AREAS. IMO, W-OFDM / V-OFDM is not a problem for QCOM, because the mobile market is absolutely massive around the world, years of work has already been done reducing the problem to robust ASICs, and I think the main market for HDR is in boosting the speeds in this massive mobile market. John

To: Bux who wrote (3740)	11/29/1999 8:59:00 AM
From: quidditch	Respond to of 13582

Maybe the kind of rake receiver it uses does not infringe Q patents, or the signal processing aggregation is based on an entirely different approach to signal processing. Maybe engineer can set us straight? Steve

To: Bux who wrote (3740)	11/29/1999 10:55:00 AM
From: idler	Respond to of 13582

VOFDM = vector orthogonal frequency division multiplexing. An "orthogonal" technology. Few weeks back, I noted Dr. J. spoke of "orthogonal" technology as a possible alternative to CDMA. "lkj" replied that Dr. J's reference to "orthogonal" technology was to CDMA; "lkj" stated that the codes used in CDMA are "orthogonal." I am still perplexed, however, because it really seemed Dr. J was mentioning "orthogonal" as an alternative to CDMA, not as the same thing as CDMA. Now these stories about VODFM. Is this the "orthogonal" technology Dr. J was talking about?

To: Bux who wrote (3740)	11/29/1999 8:29:00 PM
From: Boplicity	Respond to of 13582

Bux, Not with the Pizza size antennas they are going to use. Greg

To: Bux who wrote (3740)	11/29/1999 8:47:00 PM
From: Clarksterh	Respond to of 13582

Bux - . How is this frequency division solution for multi-path interference differ from QCOM's other than that it's designed to work in a fixed environment. It seems very similar in the way it uses digital signal processing to combine multi-path signals. CDMA deals with multipath by 'knowing' what the relative delay is for each of the paths. OFDM doesn't know anything - it just leaves a gap big enough that there is no uncertainty which bit it is that the user is recieving at any given time. As for OFDM somehow being capable of mobile just because it is multipath resistant, the two have very very little to do with one another. CDMA is orthogonal in code, which is time dependent. OFDM is orthogonal in frequencies. Thus time mismatches in CDMA (as almost unavoidably happens on the link from users to basestations) hurt capacity. Same with frequency mismatches (i.e. Doppler shift for moving users or bounces off of moving targets) for OFDM. Clark