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WHAT IS ABIS GROOMING AND CHANNEL GROOMING ?
Kindly explain in detail .
I want to know about in which condition we use sdh & pdh link.
Bhupendra,
PDH link is used for low capacity. A PDH link has from 4E1 up to 16E1s or even 32E1s depending on vendor.
While SDH link is used for high capacity. An SDH link has from 1xSTM-1(63E1s) up to 8xSTM-1 (8x63E1s), also depending on vendors.
Usually SDH links are used for backbone network, while PDH links are used to connect BTS with Backbone sites or BSC.Pls can someone state the relationships btw BSC and the RNC.
Okechukwu,
No interface between RNC and BSC. All messages between those 2 equipments are transferred through the MSC.
regards
pixAbis Grooming is when you use one E1 to groom more than one site together, By meaning the 32 channels of 1 E1 are divided for more than one BTS.
For example if configuration of 2 sites is only 900 1+1 than it only requires 4 channels for TRX and 1/2 Channel for OMU signaling and 1 channel for TRX Signaling, assumin 32 bit for all signaling channels.So we can use the remaining to groome (Add) another site to this E1.
This is not recommended unless you have no capacity on your PDH link.
Usually used for road sites.
WHAT IS ABIS GROOMING AND CHANNEL GROOMING ?
what is sdh&pdh?explain
TO Anuj:::
1 E1 is having 32 time slots ( each having 64 Kbps).
& 1 TDMA TRX supports 2 slots of E1 i.e 128 Kbps, also 2 E1 time slots used in Synchronisation & Signalling.so Maximum 15 TRX can be run on 1 E1
the E1 can carry more than 13TRX it depends on the LAPD that you use or the mapping of the SDCCH on the frames, so the E1 can carry 15TRX (LAPD multiplexing) that means that the SDCCH channels would be multiplexed with the BCCH, and by ussing half rate we can encrease it to 18TRX
The guy considered about E1 speed (Why),
One E1 has the speed of 2MBPS. The “why” is as under:
1. Human voice has frequencies upto 20KHz. Most of the “Information” is contained in frequencies 300Hz to 3700 Hz. So it is worth shedding up the rest of frequencies for effective use. This is done using band-pass filters.
2. Sampling is done, and according to sampling theorem, sampling frequency should be min 7.4KHz (ie, 2*3.7KHz). Standardization has been at 8KHz, ie one sample per 125us.
3. Then Quantization and Coding is done, converting one sample into a 8bit code. Therefore, one 8 bit code every 125us, or 64KBPS for one voice channel.
4.One E1 has 32 time slots with 8 bits each. Hence bit rate for an E1=
32 TS X 125us X 8bits= 2,048,000 bits/s
=2 MBPSactually starting we will use PDH link only.as on increasing the dependancy or capacity on that PDH link then we will upgrade from PDH to SDH to get more E1s.
what is the use of HSL and LSL links which we made in TRC and MSC
What is ater & what is the function of BSC node.
hi,
Ater means, the interface between BSC and TCSM.
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