1, CDMA: It is a new and mature wireless communication technology developed on the spread spectrum communication technology, a branch of digital technology.

2.TDMA: Time is divided into periodic frames on a broadband wireless carrier, and each frame is divided into several time slots. Each time slot is a communication channel allocated to users.

Second, the principle is different.

1, CDMA: Based on spread spectrum technology, the information data to be transmitted with a certain signal bandwidth is modulated by a high-speed pseudo-random code with a bandwidth much larger than the signal bandwidth, so that the bandwidth of the original data signal is expanded, and then it is modulated by a carrier wave and sent out.

2.TDMA: According to a certain time slot allocation principle, the system enables each mobile station to send a signal (burst signal) to the base station only according to the specified time slot in each frame, and the base station can receive the signal of each mobile station in each time slot without interference.

Third, the characteristics are different.

1, CDMA: The receiver uses exactly the same pseudo-random code, performs correlation processing with the received bandwidth signal, and replaces the wideband signal with the narrowband signal of the original information data, that is, despreads, thus realizing information communication.

2.TDMA: TDMA uses different time slots to distinguish channels of different users. On a frequency channel, it can be divided into multiple time slots. Time slots are also called physical channels. Each physical channel can only be used for the service transmission of one user at the same time.

Baidu encyclopedia -CDMA

Baidu encyclopedia -TDMA system