Friday, September 17, 2010

LTE Migration Paths

I found a nice chart in the latest 3G Americas report (Transition to 4G: 3GPP Broadband Evolution to IMT-Advanced), showing the different migration paths to LTE.

Tuesday, June 29, 2010

LTE and LTE-Advanced IPR Analysis

A very detailed IPR analysis for LTE and LTE-Advanced that I found on Slideshare.

Wednesday, June 16, 2010

Ian Harris, R.I.P

Ian Harris, one of the key contributors to the original 3GPP SMS specifications, passed away last week. Ian was one of the SMS pioneers and passion for all things related to SMS remained undimnished over the years. I had a first-hand experience of this last year while working on a proposal for support of SMS in Indian languages in 3GPP standards. He proved to be of tremendous help at every stage of this long and, at times, frustrating process. Starting from putting me in touch with other SMS experts, helping prepare the formal proposal, then ensuring that his colleagues backed us during the 3GPP meetings, presenting a contribution on our behalf when I was unable to travel to one of the meetings, arguing in favor of having Indian language character tables and much more. All this just because he was passionate about SMS and wanted it to evolve in order to meet the demands of its users around the world. I never met him in person but having exchanged many many emails last year, I considered him to be a friend and well-wisher. We were due to meet last summer during my trip to UK but it did not work out. This may be one of my life-long regrets.

Ian was a well-known figure in 3GPP circles, having worked for years in different working groups. A tribute to him has been posted on the 3GPP website.

Monday, June 14, 2010

Note of caution: HSPA, WiMAX, LTE comparisons

There is feverish speculation in the media regarding the BWA plans of RIL. Among the many articles in the media, one in particular caught my eye. DNA India carried a report, apparently based on an investor briefing from Reliance. According to this article:

“HSPA carries 2.88 bits per hertz, whereas Wimax carries 5.6 bits and (the future) LTE would carry 16.32 bits per hertz,” RIL said.

These numbers should be treated with caution for several reasons. Firstly, peak data rates vary between different releases of the same technology. It's quite obvious that the HSPA rate quoted above is for Rel-6, the very first generation of HSPA systems. Since then, advanced versions of HSPA have been developed and normalized data rates as high as 8.1 bits per second per Hertz are now supported (in HSPA Rel-8). Secondly, the peak rate calculation depends on a number of factors such as antenna configuration, modulation scheme, code rate etc. The figures quoted above for LTE are most probably for a 4x4 MIMO configuration whereas for WiMAX, these are surely for 2x2 antenna configuration. Hence, a direct comparison is not really meaningful.

BTW, the correct units are bits per second per Hertz!

Saturday, June 12, 2010

So much rubbish on LTE/WiMAX in Media

Ever since the 3G/BWA auctions started, the media has been hyper-excited and reporters are making outlandish claims regarding what 3G/BWA technologies can (and can't) do. Yesterday, after the BWA auctions were over, mainstream business and news channels had so-called experts still talking as if BWA and WiMAX are one and the same thing. Then, I happened to see some news articles which I found some amusing stuff.

Sample 1: Economic Times

LTE is a technology patented by Qualcomm, like CDMA for cellular telephony which is what Reliance chose when it started services under Mukesh Ambani. Reliance Communications has since launched parallel services in GSM.

Using this technology the company will needs to deploy fewer base stations, or points from which wireless signal is emitted because a single point covers 50 km on an average. “RIL will save on both tower leasing costs and electronic equipment cost,” said a regional telecom head at an international research firm.

Sample 2: Business Standard

LTE would have faster data speeds as compared to WiMax. Besides, voice services can also be launched through LTE and it would have a wider coverage area.

Sample 3: Business Standard

As BWA spectrum ensures higher speeds, it can support even voice calls. The high bids indicate broadband is not the only objective. “The bidding is being done for the spectrum as a whole, with just a BWA business plan now,” said Mrityunjay Kapoor, country head, Protiviti India. Experts also believe that using BWA spectrum for voice can lead to more efficient use of the spectrum.

This is just a small sample and such nuggets of information are spread all across the news pages. Is this down to lazy journalism or do we have a shortage of real experts on wireless technologies?