Basic Communication Knowledge (I)

1. Common 2G wireless communication protocols: GSM frequency division multiplexing <. txt>

(GPRS/edge and CDMA 1X code division multiple access, slow transmission speed)

2.

3G data communication bandwidth is generally above kb/s. There are three common standards: <. jpg>

WCDMA, CDMA, TD-SCDMA

3.

4G can be downloaded at a speed of Mbps and uploaded at a speed of 20 Mbps <. Avi>

Current 4G standards: WiMAX, HSPA +, LTE (3.9g), advanced and wirelessman-advanced

4.

CDMA: (Code Division Multiple Access) China Telecom 2G cnetwork

GSM: (Global Connect) China Mobile 2G and China Unicom 2G network

GPRS: General Packet service, a universal wireless grouping service, is a wireless grouping Exchange Technology Based on the GSM system.

5.

NodeB is a 3G wireless communication base station.

Enodeb: evolution NodeB, LTE Basic Station

6.

1g analog network mobile Circuit

7.

Rule makers in the communications industry-3GPP

8.

CDS: group data service

CDN: grouped data network

Pdn: Public Data Network

ISDN: Provides end-to-end digital connections for integrated business Digital Networks

9.

CS: circuit switch: mainly for voice services, as well as some circuit-based data services, such as eg Fax

PS: Packet Switch group switch: common data services, including streaming media services and VoIP

Some networks, such as VLAN and LTE, do not have CS services. Their voice services can only be implemented through VoIP.

IMS: supports multimedia and digital services and can be connected through gateways. It is carried by an IP group network.

10.

Imsi (International Mobile User identification code): the unique identifier of the SIM card stored in the SIM card

Msisdn (mobile identification number): mobile phone number

Imsi = MCC (mobile country code: China is 460) + MNC (mobile network number: 00 Mobile GSM \ 01 Unicom \ 03 Telecom) + msin (Unique Identifier ms in plmn: 02 Mobile GSM \ 07 mobile TD)

Msisdn = Cc (Country Code: 86 in China) + NDC (domestic destination code) + Sn (user number)

NDC + SN: mobile phone number

11.

Fixed Network is a fixed telephone network. A user is a fixed phone.

Basic Communication Knowledge (I)