What’s The Difference Between CDMA and UMTS?

Now that the Verizon iPhone is being sold on a different network, questions arise on the difference between Verizon and AT&T’s 3G networks. AT&T happens to use a wireless technology called UMTS and Verizon uses CDMA.

AT&T’s method uses Universal Mobile Telecommunications System. UMTS is built on the Global System for Mobile Communications (GSM) standard, which is the basis for Enhanced Data rates for GSM Evolution (EDGE). AT&T network shares lots of these traits so the iPhone and other phones on the AT&T network are able to travel around the world and be compatible on almost any network.

GSM and UMTS technology is used worldwide. Meaning, UMTS phones can easily be moved from one UMTS network to another, making them perfect for international use.

On the flip side, Verizon uses Code Division Multiples Access (CDMA); this type of network utilizes bandwidth more effectively than other network times and is often considered more efficient. The advantage CDMA has over UMTS callwise is soft handovers. Instead of switching from one tower to the other, CDMA can receive signals from multiple towers simultaneously. This not only lowers dropped call rates, but the switch is smoother and almost undetectable.

Both phones have advantages and disadvantages. For one, CDMA can’t use a SIM card and switching from handset to handset is difficult. UMTS devices also tend to have faster download and upload rates over CDMA. Where CDMA ultimately lacks is the ability to carry voice and data simultaneously. It cannot be done; AT&T phones can have a call and surf the Internet, but Verizon phones can only do one at a time.

A vast majority of the users on both networks will not notice any difference and only the most advanced users will be able to notice the differences. Calls in general will not drop as frequently on the Verizon network. AT&T does have slightly faster 3G speeds but it isn’t noticeable. And last, AT&T network is only able to take voice calls and surf the Web at the same time.

These results and differences won’t last for long. Verizon’s new LTE network is supposedly able to handle both voice and data at the same time and will bring even faster 4G speeds to the table. For now you have your information and users can decide which service they find better.

26% Of AT&T iPhone Customers Planning To Switch To Verizon

A recent survey done by ChangeWave Research indicates that more than one-in-four, about 26% to be exact, will switch to the new iPhone 4 within 90 days of Verizon releasing the phone later this month.

During the survey, ChangeWave Research also interviewed people from other wireless networks, 15% of T-Mobile and 10% of Sprint said they had plans on switching wireless providers in the next six months. Almost unanimously, AT&T users complained that there wireless coverage was poor or dropped calls, and was thus the reason for there explanation on switching. Since the introduction of the iPhone on AT&T users have not stopped complaining about customer service and coverage problems in their area.

The data also suggests that within the first year of the iPhone’s Verizon launch another 31% of AT&T customers will be switching carriers to the new Verizon iPhone.

AT&T though has one tiny bright spot to be somewhat proud of, their dropped calls reduced from 6% to 4.7%, which is a pretty significant drop, compared to Verizon’s 1.7% of dropped calls. The findings suggest AT&T is now taking concrete steps to try to improve long-standing service issues. It is not doubt that the Verizon iPhone is causing a major shift in the wireless industry, and for the moment all that momentum clearly favors Verizon.

Since the AT&T iPhone launch, all networks fell in shame of AT&T’s shadow, until now. With the upcoming sale of the iPhone 4 on Verizon the wireless revolution may be at a change for the better, we are already seeing predictions from a CDMA iPad to be coming soon as well. This is also wonderful news for any customer of AT&T because more people switching means less traffic on the network and the phone lines will open up and hopefully not drop anymore calls.

Only time can tell now what happens to the Verizon iPhone.

Three iPad 2 Variants To Be Released In 2011

By now we are all aware of the two current iPad variants, the lower priced Wi-Fi iPad and the UMTS (Universal Mobile Telecommunications System) iPad. We have been well aware of both of these iPads for a long time. Now, according to the popular rumor mill site DigiTimes, there will be another iPad variant coming into game with the iPad 2 release in 2011.

In the DigiTimes article, they report that the iPad 2 will include a Wi-Fi, UMTS, and a CDMA variant. With the added integration of a CDMA chip, Verizon-like carriers will be able to provide the iPad on their wireless network. Apple has orders to ship about 500,000 units in January with shipment ratio of Wi-Fi, UMTS and CDMA models at 3:4:3.

In addition to the new wireless functions, Apple is also working on an improved anti-smudge and anti-reflective system for the upcoming iPad 2. Currently 60-65% of current iPad shipments are 3G models, indicating that most of the iPad consumers prefer the 3G model of the iPad.

Verizon iPhone Rumors Almost Confirmed

Verizon iPhone Rumors almost confirmed — we are talking about 99.999% confirmed here. According to DigiTimes, Apple has a shipment goal of around six million CDMA iPhones scheduled for early 2011. For even the moderate geek, you know that AT&T is a GSM network. That means that Verizon is finally getting a piece of the iPhone 4.

The DigiTimes article reports that the large shipment of CDMA iPhones will be going to North America and Asia Pacific. As we have talked about in the past, Verizon has gone through a major overhaul of its CDMA network. Gearing up with 4G LTE, Verizon’s network is finally able to take a huge stress attack of iPhones to the network.

If the Verizon iPhone rumors prove true in early 2011, it will be a big relief for users. There have been numerous complaints about AT&T’s coverage and support. According to a Consumer Reports survey, AT&T ran dead last in customer satisfaction.

The promising 4G LTE Verizon network and reliability go well with the iPhone 4. The only surprise that would come out of this story is if Apple doesn’t release an iPhone for Verizon in the first quarter of 2011.

Straight Talk – More Phone Options Including Verizon, AT&T & T-Mobile Services

Straight Talk continues to expand their offering of not only cell phones, but also the carriers they are using. Besides using the Verizon network for their CDMA services, the company has added GSM networks from AT&T and also T-Mobile, depending on the service quality in your area. Last night I contacted Straight Talk support and asked for clarification on the networks they are currently using. I received this reply:

We would like to inform you that Straight Talk is using the CDMA and GSM technologies. The Straight Talk phones that are under the CDMA network do not have a SIM Card. These phones are powered by Verizon. However, the phones under the GSM network have a SIM Card and they are powered by AT&T or T-Mobile (depends on the best working carrier on your area).

Please be advised that the Nokia E71 and Nokia 6790 are powered by AT&T only. Thank you for your inquiry.

One of the questions that has been asked by readers is if you can take a non Straight Talk phone [GSM only since CDMA phones do not have Sim cards] and use the phone with the Straight Talk service. Some have responded that they have had success using a ST SIM card in another unlocked phone and have indicated it worked for them.

However, the general consensus is though the phone may work, when you leave the area, the phone may not work for roaming.

My advice is this. Stick with a Straight Talk enabled phone for the best results. But if you have a GSM phone that you just have to have, you can try using the ST SIM but results are going to vary widely, depending on the make and model of the phone.

There is a lot of misinformation about ST phones. One reader noted the Nokia E71 works on both Verizon and AT&T which is false.

Comments welcome.

iPads With Multimode CDMA-GSM Chips

Imagine iPads with multimode CDMA-GSM chips. Clearly, what would be thought of as the holy grail of tablet computing as it would mean the mobile wireless option would be functional anywhere the user happens to be, regardless of mobile technology at play in the region where someone wanted to use the iPad.

There is a lot of logic in this line of thought. And assuming Apple can pull it off, it’s a big win not just for multiple countries, but likely for us here in the States as well. Further expectations for these new iPads include a front facing camera and a unibody construction.

It’s speculated that the CDMA-GSM iPad is not merely a stab at gaining more traction in the international market, but also locking themselves in deeper here within our neck of the woods as well.

Indian Firms Seek A CDMA iPhone

There should be an image here!Ah yes, the famed and mythical CDMA iPhone that will someday over the rainbow make a magical, leprechaun-like appearance. About the only truth in that is it would cost a pot of gold to get this to completion based on progress I’ve seen thus far. Nevertheless, this article indicates that Indian firms are “in talks” to get their hands on an iPhone supporting CDMA technology.

Now let me explain why I think India may have a real shot of making this happen. If going with CDMA is what it takes to get India on board with the iPhone in a very big way, you better believe Apple would be all over that. Next to China, they are one of the fastest growing mobile markets out there to date.

Once you bundle this with the expected revenue to be had by all involved, I think we might see India as the country that pushes Apple into going CDMA just a little quicker. GSM has been fun on AT&T here in the States and all, but I think it’s time to diversify a little bit. We’ve been hearing about how the iPhone is going to be coming to Verizon’s own CDMA network. Maybe this will finally be a way to make that happen?

Wi-Fi-CDMA – Frequency Hopping Vs. Direct Sequence Spread Spectrum

The animated TECHTip is available here.

There are two basic types of CDMA [Code Division Multiple Access]: FHSS [Frequency Hopping Spread Spectrum] and DSSS [Direct Sequence Spread Spectrum]. Direct Sequence is used in Wi-Fi-Wireless Fidelity or 802.11. Each Wi-Fi system uses the same set of frequencies in the 83.5 MHz of available frequencies available in the 2.4 GHz band. That is, the IEEE 802.11b standard defines 11 possible channels (frequencies bands) available for use numbered 1-11.
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