Purchase guide learn about three wireless network card types

There are many articles about wireless network interfaces and wireless network interfaces. Let's take a look at the wireless network card type. So what are the functions of these types? Which one is better?

Wireless Network Adapter, as its name implies, is a network adapter that does not need a network cable. It is a widely used Internet medium in wireless wide-area communication networks. Currently, only China Mobile's GPRS network and China Unicom's CDMA (1X) network are available in China. Therefore, common wireless network adapter types include CDMA wireless network adapter and GPRS wireless network adapter. There is also a CDPD wireless network adapter.

Wireless network adapter type 1: CDMA

CDMA (Code Division Multiple Access, Code Division Multiple Access) wireless network adapter is an Internet connection device for China Unicom's CDMA network. CDMA allows all users to use all the frequency bands at the same time, and treats signals sent by other users as miscellaneous without considering collision.

Wireless network adapter type 2: GPRS

GPRS network adapter is a wireless Internet access device for China Mobile's GPRS network. GPRS is called General Packet Radio Service in English. The Chinese meaning is "General grouping wireless Service", which uses "Packet switching" Packet-Switched) concept is a set of wireless transmission methods. The so-called Packet Exchange is to encapsulate the Date into many independent packets, and then send these packets one by one. The form is similar to sending packages, the advantage of Packet Exchange is that bandwidth is occupied only when data needs to be transferred and can be priced based on the amount of data transmitted. This is a reasonable billing method for users, because most of the time bandwidths for data transmission such as the Internet are reset.

Compared with the original GSM dial-up method, GPRS is a group exchange technology, it has the advantages of "real-time online", "pay-as-you-go", "Quick Logon", "high-speed transmission", and "easy switch.

Wireless network adapter type 3: CDPD

CDPD Cellular Digital grouping Data-Cellular Digital Packet Data) adopts the grouping Data method and is currently recognized as the best Data communication procedure for wireless public networks. It is an open system structure based on TCP/IP, it combines open interfaces, high transmission speeds, user unit determination, air link encryption, air data encryption, compressed data correction and re-transmission, and the world's standard IP address mode for wireless access, provides seamless connection and multi-protocol network services for the same-layer network. CDPD features a high speed of 19.2 kbps) and high data security. It supports cross-Area User Switching, full-network roaming, broadcast, and group calling, and supports data users with a mobile speed of up to 100 km/h, it can be interconnected with public wired data networks.

CDPD is particularly suitable for scenarios with multiple user points, wide distribution, mobile, short message usage, and high frequency. Currently, it is mainly used in the following fields: financial transactions, transportation, telemetry and remote monitoring, and mobile office.