- This topic has 10 replies, 1 voice, and was last updated 14 years, 4 months ago by yan.
30th March 2007 at 11:27 #46928vivekGuest
can anyone will tell me about E1’s
which is very frequently used word in telecom industry and its utility.30th March 2007 at 16:36 #46929vasuGuest
E1s are 2MBPS DIGITAL LINES WHICH CARRY 30 VOICE CHANNELS OR
2048 KBPS OF DATA. THESE ARE
PRIMARY LINES EXTENDED TO CUSTOMERS AND MULTIPLEXED FURTHER
TO FORM HIGH SPEED DATA TO BE
SENT ON OPTICAL CABLES FOR LONG
DISTANCE.3rd April 2007 at 13:51 #46930SameerGuest
E1 is 2.04MBPS bandwidth in short
We will have 31 timeslots in one E1,normally for TDM connectivity 31 timeslots can carry 31 calls at a time,13th April 2007 at 18:00 #46931VKGuest
Only 30 time slots can carry useful data in ordinary configurations.26th April 2007 at 09:22 #46932K.JGuest
it depends , if a E1 is configured as C7 NLD trunk , all 31 can carry voice ,or if as a CAS then it is only 30, if its a PRI then also 30, but avilable usable Time slots are 31.8th May 2007 at 15:04 #46933DudeGuest
Basically, like everyone else has said here, an E1 is a simple coax cable that can carry up to 2048Mbps. Since each Timeslot (TS)/voice circuit has a bandwidth of 64Kbps, it means that each E1 can have up to 2048/64 Time Slots, which gives 32 Time Slots. Time Slot 0 is usually used for frame alignment, which leaves you with 31 usable time slots – except in the cases that have already been stated (CAS, PRI, etc).17th July 2007 at 21:28 #46934finnGuest
E1s or T1s were taught in the university..
it can be transmitted also via two-wire balanced 120ohms18th July 2007 at 08:38 #46935turd!Guest
E1 has 32 timeslots as has been said..
Usually 1 timeslot is allocated for signalling and 1 for synchronization that is why some claims 30 timeslots, some cliimed 31 timeslots.
With regards to call capacity, for E1 each timeslot has 64 kbps and a certain voice call (VC) is encoded with 16 kbps full rate and 8 kbps in half rate mode.
So considering 1 TS in E1, in can carry up to 4 VC at fullrate. With 30 TS a certain E1 can carry as much as 120 calls.(4 VCperTS x 30TS)18th July 2007 at 12:37 #46936BikramGuest
Can anybody tell how to calculate Erlangs in the CDMA system ?
How do I know that how many erlangs is generated by a BTS.19th July 2007 at 07:04 #46937finnGuest
ah that’s advanced you used E1 in an application now, that’s how it is in GSM the like. that’s true with the wireless applications..
so how about concentrated, uncon and multiplexing? how is it done?
lets do it like this…
1 TDMA frame of, be it E1 or T1 its still 64kbps… so usually 64kbps for a voice call in PSTN that’s why you have a 52kbps modem which is under 64kbps…
1 TDMA frame is divided into 4 TS + another 4TS from the next TDMA frame and you will come up with the GSM’s 1 TRX which is 8TS ~ 7 to 8 VC..19th July 2007 at 08:26 #46938yanGuest
Please tell us what you mean by C7 NLD, CAS & PRI