what is CDMA?is it possible multimedia transcations in this technology?

Question

i am doing project on this ?so please help me friends?

i need what are the facilities available in CDMA?

Answer 1

check this web link, theres a detailed explaination on CDMA.

Answer 2

CDMA is "code division multiple access".

CDMA is a method for multiple devices to share a particular resource. In particular, CDMA lets multiple cell phones share bandwidth from a cell tower.

Alternate multiple access methods split bandwidth up in time or frequency slices. For example, two phones sharing the same frequency take turns when using it *OR* just use different frequencies and don't worry about taking turns.

CDMA lets multiple phones use the same frequencies AT THE SAME TIME. Thus, it's a "spread spectrum" technology. The idea is to give each cell phone a different set of "codes." For example, let's say phone A transmits using waveforms that look square and phone B transmits using waveforms that look triangular. Phone A will be able to disregard anything triangular and only pay attention to square waves, and vice versa for phone B. This method is equivalent to phone A speaking Russian and phone B speaking Italian. The two languages are so different that it's easy for phone A to block out phone B's information as noise (and vice versa).

CDMA is a communications technology. It's very generic. A list of technologies that use CDMA would be too numerous and not very useful. If you have some raw bandwidth allocated to you, YOU could use CDMA to transmit different data to different devices of yours.

Answer 3

Collision Detection Multiple Access. Ethernet is based on this idea. Everybody shares the same wires. If you want to transmit, you listen first to see if it is busy. If not, then blurt out your message, addressed to your recipient. If somebody also transmits at the same instant, you have a "collision". Both parties observe the collision and stop their transmissions and then (here is the key) wait awhile before re-trying. And the time delay changes each time it happens so it is unlikely that they will collide again. There is no "master" controlling the communications, so it is called a "peer" system, where all are equal. It is a lot like conversation around the dinner table, actually, and all the computer communications systems I know have their counterpart in human communication.

Answer 4

CDMA is one of the cell phone technologies for transmitting signals and keeping track of which phone goes with which signal.