CPRI Cable Function and Details in Telecom

In this post we will discuss about the the CPRI (Common Public Radio Interface) cable, its function and it various details in telecom.

1. Introduction:

CPRI stands for Common Public Radio Interface. It is the world standard interface defined for Radio Equipment Controllers(REC). REC are basically Base Band Unit(BBU) and Remote Radio Unit(RRU) in telecom industry. CPRI standard is followed by top leading telecom equipment manufacturer like Huawei,Ericsson,Nokia,NEC, ZTE and many more.

2. CPRI Functions:

CPRI is optical fiber cable that carry signals whether it is control signal or message signal. Control signals are the controlling signal that carry information of the status of the equipment installed in the BTS and other various traffic related signals whereas message signals is the information related to user communication. Thus the function of CPRI cable in telecom is very important.

CPRI supports multi mode communication and doesn’t support single mode communication. In optical fiber, single mode communication is that where single light is transmitted between two radio equipment for communication and data transfers. Whereas multi-mode supports more than one light to be transmitted through the same single optical fiber link at a time. Thus multi-mode is used for communication in very short distance whereas single mode is used for long distance communication because of low loss in single mode fiber.

3. Different connector types:

Below is the chart of the Optical fiber connector types: (source:Alibaba):

Among most of the connector types, LC-Duplex is very common in Telecom Industry for connecting BBU and RRU. 

LC-(Simplex and Duplex) is a push on,pull-off, multimode or singlemode fiber type of connector containing a standard RJ 45 telephone plug housing with a ceramic ferrule in a simplex or duplex plastic housing; SFF(Small Form Factor)and SFP(Small Form Pluggable) designs are suitable for high density interconnection and also useful for instrumentation and test equipment interconnections. It have insertion loss of  0.1 to 0.5 dB.

About CPRI Cooperation:

The Common Public Radio Interface (CPRI™) is the successful industry cooperation defining the publicly available specification for the key internal interface of radio base stations between the Radio Equipment Control (REC) and the Radio Equipment (RE). The Parties cooperating to define the CPRI Specification and are now encompassing Ericsson, Huawei, NEC and Nokia. Nortel contributed as member of the CPRI cooperation to CPRI Specification versions 1.4, 2.1, 3.0 4.0 and 4.1 and left the cooperation in December 2009.

CPRI cooperation is now working on increasing efficiency and the inclusion new features which will be published in new versions of the CPRI specification in due time.

Above all, If you find this post useful, please give thumps up. If something is missing or if you want more concept, ideas and details of other telecom equipment’s please leave comment in the comment section below. I will  include those topics in my coming post. Thank you.