-
Anonymous users2024-02-07i.e. CDMA. It is a kind of addressing method in mobile communication, and I can't tell you the specifics. Anyway, it's a kind of technology, you can get it at once. ^_
-
Anonymous users2024-02-06Code division multiple access: a new wireless communication technology.
-
Anonymous users2024-02-05Code refers to the way it is encoded.
I've heard of code division multiple access, but I haven't heard of code division multiple access. In fact, "code division multiple access" is "code division multiple access".
Code division multiple access: The frequency of the signal is the same, and the channel is multiplexed through different coding methods, which is called code division multiple access. That is, the function of "one way" to "multiple roads" is realized. You just need to think of "address" as "signaling pathway".
Similarly, time division multiple access (TDMA) and frequency division multiple access (FDMA) are similar, and CDMA is code division multiple access.
-
Anonymous users2024-02-04Strong anti-interference ability. This is the basic feature of spread spectrum communication, which is incomparable to all communication methods.
Broadband transmission, strong anti-fading ability.
Due to the use of broadband transmission, the power of the useful signal transmitted by the field in the channel is much lower than the power of the interfering signal, so the signal leakage call seems to be hidden in the noise; That is, the power spectral density is relatively low, which is conducive to signal concealment.
The correlation of the spread spectrum code is used to obtain the user's information, and the ability to resist interception is strong.
-
Anonymous users2024-02-03Code division multiple access: a brand-new wireless telecommunications technology.
-
Anonymous users2024-02-02Spread spectrum codes are used to divide channels, and scrambling codes are used to distinguish between users and cells.
-
Anonymous users2024-02-01Because the CDMA system has the ability to resist perceived interference, anti-narrowband dismissive interference, anti-multipath interference, and anti-multipath delay expansion, and at the same time has the advantages of improving the communication carrier kernel of the cellular system and facilitating the coexistence and transition of analog and digital systems, the CDMA digital cellular system has become a strong competitor of the TDMA digital cellular system.
The IS-95 CDMA and CDMA2000 1X cellular systems are two typical CDMA systems, and their corresponding operating frequency bands are 870 894MHz uplink (mobile station transmitter and mobile station reception) 825 849MHz and duplex interval is 45MHz. The IS-95 CDMA and CDMA 2000-1X systems with cellular architecture use code division multiple access technology, the carrier frequency interval is the chip rate, and each cell can use the same carrier frequency, that is, the frequency multiplexing factor is 1
-
Anonymous users2024-01-31Code division multiple access: a new wireless communication technology with wide code ridge and late brightness.
In a data communication system or computer network system, the bandwidth or capacity of transmission often exceeds the need to transmit a single signal, and in order to effectively use the communication line, it is desirable to transmit multiple signals on one channel at the same time, which is the so-called multiplexing technology (multiplexii1g). The use of multiplexing technology can combine multiple signals to transmit on a physical channel, which can greatly save the installation and maintenance costs of cables when transmitting over long distances. Frequency Division Multiplexing (FDM) and Time Division Multiplexing (TDM) are two of the most commonly used multiplexing techniques. >>>More
1, a, the optical transmission system consists of 3 parts, optical fiber transmission medium, light source and detector. 2,a3,b4,d,multiple,5,a can be achieved through the port number that does not pass 5,aI wish you a smooth exam.
First, the field of communication is developing rapidly.
If we were to pick the technology that has grown the fastest in the last 20 years, it would be communication technology. With the emergence of communication and various new technologies, it involves a wider range of fields, such as telecommunications, networks, home appliances, finance, medical care, aviation, industry and so on. >>>More
Optical fiber communication technology stands out from optical communication and has become one of the main pillars of modern communication and plays a pivotal role in modern telecommunication networks. As an emerging technology, optical fiber communication has developed rapidly and widely in recent years, which is rare in communication, and it is also an important symbol of the world's new technological revolution and the main transmission tool of various information in the future information society. >>>More
Don't eat fried foods. Don't eat cold, popsicles, drinks. My mother often made me soybeans and pork belly to cook together, and my mother said that it was for stomach.