Some FAQs about PCs you wish you knew before you bought it!

Saturday, January 29, 2011

A comparison of various wireless network techn...Image via WikipediaQ: What can you tell me about 3G, UMTS, W-CDMA, HSPA, GSM, CDMA, LTE, and all that?

A: Oh, boy, that's a long story.

First, 3G is a generic term used by marketing. ITU, the standards body, calls it IMT-2000. That is the FORMAL definition of "3G".

Within IMT-2000 there are 2 "families", 3GPP, and 3GPP2. 3GPP means "3rd Generation Partnership Project". The two families are working on different but competing standards.

Within the 3GPP camp, the overall term is UMTS, or "Universal Mobile Telecommunication System" but it is sometimes called 3GSM, as it is derived from GSM (a 2G standard). However UMTS is the official term used by 3GPP to describe the RADIO technology. The overall tech scheme is W-CDMA, or wideband code division multiple access. It is a way to push multiple pieces of data simultaneously over multiple frequencies (sometimes called "spread spectrum"). 

Within UMTS, there are various technologies and "releases" introduced over time to improve the standard. HSPA, or High Speed Packet Access. Within HSPA, there are two versions, Uplink, and Downlink. So you get HSPUA and HSPDA. Later revision updated that to HSPA+, and even within HSPA+ there are 3 versions, 14, 21, and 42 (refering to downlink speeds).

Within the 3GPP2 family, there is CDMA2000 and its variations / releases, which would be 1xRT, EV-DO (and its variations), and later, SV-DO.

Any way, onto 4G.  ITU approved the next generation, 4G, standard as IMT-Advanced.

LTE (Long Term Evolution) is a 3GPP standard trying to push beyond their UMTS (3G technology) by adopting some newer technology to make it "4G". It is not fully compliant with IMT-Advanced. LTE-Advanced, the next version, will be fully compliant.

WiMAX is a completely different technology. It stands for "Worldwide International standard for Microwave Access", and is based on Microwave transceivers. It can be used as broadband access in a cellphone. It is not fully compliant with IMT-Advanced as well, but next version should be.

Recently ITU gave in to phone carriers and relaxed the definition of "4G", allowing even 3G-derived technology such as HSPA+ to be called "4G" as long as it delivers significant speed increase over normal 3G data transmission rates. 

Hope that clears things up somewhat.

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Saturday, January 15, 2011

Q: What do you think will be in Apple's iPad 2 and iPhone 5?
A: Here's my predictions:

iPad 2 -- just a SD slot and dual-system CDMA/GSM 3G modem built-in. Maybe a dual-core CPU

iPhone "5" -- I think it's going to be 4S, not 5. It'll be dual system CDMA/GSM, and dual-core CPU. LTE will be for 2012 model. THAT will be iPhone 5.

To be honest, I cribbed half of the info from engadget.

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Friday, January 14, 2011

Image representing Sprint Nextel as depicted i...Image via CrunchBaseQ: Now that Verizon has the iPhone 4, what do you think Sprint and T-Mobile's upcoming announcements in February 2011 would be about?

A: The Sprint announcement will likely be the first Windows Phone 7 for Sprint 4G

And the T-Mobile announcement will likely be about their Samsung Galaxy S Vibrant 4G, which is actually capable of reaching HSPA+21 (the G2 and the MyTouch 4G are actually just HSPA+14 devices, twice as fast as regular HSPA 7 Mbps)

Why neither will have the iPhone? Because if they did, they'd be sharing the stage with Verizon.

Why Sprint and Windows Phone 7? Because so far WP7 devices are ONLY available on AT&T and T-Mobile (even the Dell Revue). Verizon don't need WP7 device since it is getting the iPhone 4. So it must be Sprint.

Why T-Mobile and their 4G? Because they need to announce something that'll lead the market, and HSPA+21 device will beat just about everything else on the market.

UPDATE: Turns out Sprint's event is for the Kyocera split-screen Android phone. Hmmm... And it's not even 4G!

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Monday, January 10, 2011


Q: Can you recommend a good password manager?

A: I like Keepass which is free, can automatically fill forms,  and if you have Android phone you can use same data file on KeePassDroid