Why Cdma Cellular services still want To Compite with GSM ,if GSM is the world leader !?

Answer 1

This is a complicated question to answer, as you are going to get people who will be for or against each of the technologies and biased to the one they prefer. I will try to give you a fairly concise, and unbiased answer:

CDMA has higher capacity for customers and bandwidth for throughput, and although it runs on a natively more complex network, ESN switching instead of SIM card switching, it also penetrates into buildings, and travels a little further with standard deployment schemes.

GSM has a lower capacity, and less bandwidth per channel/frequency and such, but its easier for the end user to swap sims and choose any phone. Since it doesnt penetrate as well, sometimes you hear about GSM networks having "worse reception" which alot of carriers solve by adding more cell sites to compensate.

Yes GSM is the world standard, but CDMA offers the cell companies more security as they don't have to worry abotu stolen handsets. Historically GSM has worked well in smaller countries like europe because they have less land to cover, and therefore can build more cell sites and get better reception, even with a less penetrating signal. In large countries like the US, CDMA has been easier to implement because it goes further per cell site, and offered a quicker buildout option.

My prediction is that you will see most companies switching over to GSM, or GSM-like standard within the next 10 years...although they will be broadband options, and next gen platforms by then.

Answer 2

Another reason why we'll continue to see GSM and CDMA in competition: expense of replacing equipment.

As it stands in the US, Verizon Wireless and Sprint have a substantial investment in their CDMA infrastructure. They like the equipment they have and the vendors who manufacture for them. If they choose to switch to GSM vendors, they probably wouldn't have the flexibility in pricing, and leverage in getting new features developed, they currently have with CDMA vendors.