E1 carrier Bit Rate

E1 carrier comes with European digital transmission format devised by the ITU-TS (International Telecommunication Union Telecommunication Standardization Sector). This name is given by the Conference of European Postal and Telecommunication Administration (CEPT). Normally E1 carrier operates on European and some Asian countries. But E1 is equivalent standard of the T1 carrier system in North American. 

E2 through E5 are carriers in increasing multiples of the E1 format. But in the Industry only E1 and E3 versions are used. Actually E1 is transmitted as 32 time slots and E3 is capable of carrying 5120timeslots.There are two time slots for framing (For synchronization) and another one for signaling (For allocating call setup). E-carrier systems permanently assign capacity for a voice call for its whole period. Therefore this makes sure high call quality because the transmission arrives with the same short delay and capacity at all times.

Here are the data rates of multiple E carriers.

E0 - 64 kbit/s

E1 - 2.048 Mbit/s

E2 - 8.448 Mbit/s

E3 - 34.368 Mbit/s

E4 - 139.264 Mbit/s

E5 - 564.992 Mbit/s

In E1 carrier there are 32 channels in the frame. The bit rate can be calculated as follows;

Time taken for the whole frame              = 125μs

Number of bits in a time slot                   = 8 bits
Number of time slot in a frame               = 32
Therefore number of bits in a frame       = 32 x 8 bits

                                                                         265 bits

We know bit rate can be achieved as follows;

                        Bit rate of E1 carrier           = number of bits /time taken

                                                                          256 bits/125μs

                                                                          2.048 Mbit/s