- This topic has 6 replies, 1 voice, and was last updated 5 years, 4 months ago by Wallis Dudhnath.
3rd September 2011 at 13:30 #67094RiskGuest
GSM has radio timeslot, what is alternative in UMTS?
GSM has user limit for each trx max 16 user per trx, what is alternative in UMTS?3rd September 2011 at 16:41 #67095paraHOGuest
You said: GSM has radio timeslot, what is alternative in UMTS?
Question: Why do you think UMTS not have radio tiemslots
You said: GSM has user limit for each trx max 16 user per trx, what is alternative in UMTS?
Question: which standard do you say state is relevant to GSM having “trx max 16 user per trx”?3rd September 2011 at 17:06 #67096RiskGuest
1. There are 8 timeslot in one trx in gsm. I asked what is the situation in umts?
2. 16 users can be established in one trx with hr in gsm. I asked what is the situation in umts?
If you know other gsm standart, then please let us know.3rd September 2011 at 18:01 #67097pixGuest
in UMTS, each user is allocated a “Code”, rather than a timeslot and a frequency (carrier).
Thanks to this code, the user is able to send its data over the whole band (5MHz by def.), and this data can be retrieved among all the other signals, thanks to this code (each code is orthogonal with each other)
your second question is : how many codes can be handled by each “TRX” in 3G. This, I don’t know. I think it is not standardized and highly depends on the capacity of the HW. It’s vendor dependent.
pix29th October 2015 at 12:17 #67098VachaspatiGuest
What is the term used in UMTS for “TRX” as TRX term is used in GSM by the vendors while Radio Unit or baseband unit used in 3G/Lte29th October 2015 at 13:12 #67099gagsGuest
UMTS has channel elements which are equivalent to time slots in gsm.
A band Channel Element is the resource base required in the Node-B to Provide for one voice channel capacity, including the control plane to Provide for one voice channel capacity, including the control plane signaling, compressed mode, the transmit diversity and softer handover. signaling, compressed mode, the transmit diversity and softer handover.1st November 2015 at 09:31 #67100Wallis DudhnathGuest
Just an add on answer to the excellent inputs. GSM is based on TDMA – Time Slots associated with a frequency. To alleviate interference a RF frequency plan is set up by the CSPs. 3G is based on spread spectrum that uses a PRBS to spread information with the allotted bandwidth. 3G is a power / bandwith intensive solution. NodeB and eNodeB (4G) is used.
VBR/ Wallis Dudhnath