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!

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?