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Member
Reputation: 64
please post UMTS interview questions
Please post UMTS questions that are likely to be asked in an interview along with the answers if possible ?
thanks in advance..
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2010-07-21 11:39 AM
# ADS
Circuit advertisement
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Member
Reputation: 408
Re: please post UMTS interview questions
some questions about WCDMA. I don´t have the answer. Only for UMTS interview example.
1 what is meaning of Ec/Io? what is the best value of Ec/Io when there is 75% of downlink load simulated, while the PCPICH power is 33dBm (total power of the cell is 43dBm).
2 how to find missing neighbor cell list during the drive test?
3 what is the relationship between "singaling flow", "counter" and "KPI"?
4. what should be the normal value range of RTWP, assume there is no any interference and any user.
5why we need the antenna isolation? how to calculate the anatenna isolation distance?
6.what is the relationship between link budget and simulation?
Last edited by mike; 2010-07-21 at 12:22 PM
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Junior Member
Reputation: 10
Re: please post UMTS interview questions
What is the main difference between RB (Radio Bearer) and RAB (Radio Access Bearer)?
Last edited by eg7014; 2010-07-21 at 01:22 PM
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Senior Member
Reputation: 591
Re: please post UMTS interview questions
Here are some more to Mike's questions:
- Differentiate between the uplink and downlink modulation techniques used in UMTS.
- What is the range of spreading factors used in the uplink and downlink?
- Differentiate between channelization and scrambling codes.
- What is softhandover? How does it impact performance and network capacity?
- What is compressed mode operation? How does it impact cell capacity?
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Member
Reputation: 64
Re: please post UMTS interview questions
Thanks to all for the questions..But can you provide answers to these questions ?
Differentiate between channelization and scrambling codes?
- Differentiate between the uplink and downlink modulation techniques used in UMTS.
- What is the range of spreading factors used in the uplink and downlink?
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Senior Member
Reputation: 591
Re: please post UMTS interview questions
Originally Posted by
coursekec
Thanks to all for the questions..But can you provide answers to these questions ?
Differentiate between channelization and scrambling codes?
- Differentiate between the uplink and downlink modulation techniques used in UMTS.
- What is the range of spreading factors used in the uplink and downlink?
channelization vs. scrambling codes:
The former spreads the signal; has good cross correlation properties; orthogonal to one another, variable code
The latter does not spread the signal; has good auto-correlation properties; almost orthogonal to one another; not variable in size.
Uplink vs. Downlink modulation:
Downlink uses QPSK
Uplink uses Dual BPSK (biomedical compatibility reasons)
Range of Spreading Factors:
Downlink : 4 to 512
Uplink: 4 to 256
Hope it helps.
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Member
Reputation: 33
Re: please post UMTS interview questions
Originally Posted by
coursekec
Please post UMTS questions that are likely to be asked in an interview along with the answers if possible ?
thanks in advance..
Hi,
Below are the questions given to me during my interview.
1. Protocol Messages between network elements
WBTS and RNC – NBAP
RNC and RNC – RNSAP
RNC and MSC – RANAP
RNC and SGSN – RANAP
2. Signaling Protocol Message between UE and RNC
RRC
3. Factors that affect HSDPA bit rate. Explain relationship
A. Modulation
B. Channel Quality
C. Number of Codes
4. Causes of HO
Just explain the events
5. What is the value for soft handover overhead
I told him that some design are 30% some are 40%
These are the things that i remember back then.
Hope this might help.
Br,
Sen
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Member
Reputation: 64
Re: please post UMTS interview questions
thanks a lot to both of you..
i've added reputation to both of you..
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Re: please post UMTS interview questions
pl give the anwsers of thses questions.
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Re: please post UMTS interview questions
Who will give answers to these questions ? pl give.
Originally Posted by
mike
some questions about WCDMA
. I don´t have the answer. Only for UMTS interview example.
1 what is meaning of Ec/Io? what is the best value of Ec/Io when there is 75% of downlink load simulated, while the PCPICH power is 33dBm (total power of the cell is 43dBm).
2 how to find missing neighbor cell list during the drive test?
3 what is the relationship between "singaling flow", "counter" and "KPI"?
4. what should be the normal value range of RTWP, assume there is no any interference and any user.
5why we need the antenna isolation? how to calculate the anatenna isolation distance?
6.what is the relationship between link budget and simulation?
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