- This topic has 6 replies, 1 voice, and was last updated 7 years, 2 months ago by Wallis Dudhnath.
7th September 2016 at 06:32 #69933DannyGuest
Kindly explain, In general, BTS generates its own Clk or use the internal Clk from BSC for synchronization? kindly share some basic document related to subject. Thanks.9th September 2016 at 09:38 #69934Wallis DudhnathGuest
Does your Network have a Synchronisation master plan?
From experience two paths (for redundancy and resilience) is used to ensure that a stable “clock” signal can be propagated to each element in the Network. One source will be from an atomic “clock”.
To reign in a fast node a PLL approach is used.
For BTS it will get a “clock” signal from a higher order element (BSC/MSC). If the “clock” signal is lost the element will become despotic, i.e. it will be at odds with the rest of the Network.
VBR/ Wallis Dudhnath16th September 2016 at 10:41 #69935DannyGuest
Thanks Mr. Wallis, kindly treat me as a novice & please explain in detail or share some basic level document related to topic. As per my understanding, BTS is expecting Clk from BSC/MSC & at BSC/MSC there is redundancy as internal/external clk.17th September 2016 at 12:40 #69936Wallis DudhnathGuest
Tried to post an update using a URL. It failed as I feel that URLs are rejected by this site.
From Google do a search for Ericsson Review and Network Synchronisation. There is a pdf file that looks at Synchronisation.
VBR/ Wallis Dudhnath19th September 2016 at 10:00 #69937Wallis DudhnathGuest
Synchronisation in Telecommunications networks (ISDN, Digital Networks, GSM, 3G, 4G, 5G, etc..) is the process of aligning the time scales of transmission and Switching Equipment (e.g. Stored Program Control nodes) so equipment operations occur at the correct time and in the correct order. Synchronisation requires the receiver clock to acquire and track the periodic timing information in a transmitted signal.
Poor synchronisation can lead to the following issues:-
– Degraded speech quality and audible clicks
– Degraded data traffic throughput
– Call setup
– Incomplete Facsimile messages
– Freeze-frames and audio pops on video transmissions
– Call disconnects during mobile call hand-off
– Partial or complete traffic stoppage
– Corrupt data sessions for 3G/4G/5G
– Errors placed in CDRs and Logs
A complete Network Synchronisation plan must be in place that looks at the Clocks (Stratum) used, Jitter and Wander
parameters, Primary and Secondary Synchronisation Clock sources, etc.20th September 2016 at 11:54 #69938DannyGuest
I really appreciate your efforts, thanks a lot.21st September 2016 at 10:16 #69939Wallis DudhnathGuest
This site does not allow URLs – XSS vector attacks.
If you look at a Computer there is a clock that is used to keep the whole system synchronised. The clock helps to operate the Fetch-Decode-Execute cycle. This is a property of a Digital system.
As a Telecommunication Network has evolved with PDH, ISDN, ATM, Ethernet, SDH, Digital Stored Program Control nodes, GSM, 3G, 4G and now 5G / IOT there has to be a tight control with how the Network is clocked and Synchronised.
It is very easy for a node in the Network to become despotic and to race ahead with it’s own clock frequency. Phase Locked Loop (PLL) is used to reign in a despotic node. This will cause issues as described in my earlier post.
To help a Network designer uses a stratum approach to source a stable (e.g. atomic clock) Synchronisation signal that can be cascaded to the lower strata.
Please keep sending your questions.
VBR/ Wallis Dudhnath
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