@@IrfanAli-nz7mb Thanks for the video. However, why did you divide RSSI by N_RB ? From the fact that max RSRQ is -3db it seems that RSSI is the sum of the total power in all the N_RBs, not per RE
I love ur training's. What is the main difference between RSRQ and SINR? From my understanding, RSRQ includes own cell load and SINR not but theoretically there is a calculation relation between SINR using RSRQ. That's where I confuse :) if rsrq is used in sinr calculation than own cell load does count. Where am I wrong ? Hope I am clear to explain :) Regards
Hi Irfan, if one RB has 4 ref signals then one ref signal should contain 25% of total energy, am I correct? But you are quoting 50%? Can you please clarify?
Dear Sir, As we known, one of difference between RSRP and RSSI is the different measurement bandwidth. RSSI is measured by full bandwidth with all RBs (1RB contains 12 REs) and RSRP is averaged power by one RE. If noise/interference is added in the full bandwidth of all RBs, why the RE that contained RS not included the power of noise/interference?
Dear Sir, Thanks and understood that RSSI also contained the energy in the reference symbol. Around 3:00, mentioned that "RSRP measures only the RS power and excluded all noise and interference power." Just wondered how RSRP can exclude all noise and interference in detailed?
1 Resource block have 12 subcarriers 7 symbols and 84 resource elements right? if there are 6 PRB's then why resource elements are 72? I know right there are 72 RE in 6 PRB's but I want to know how? I'm confused somewhere.
Each PRB has 12 subcarriers. So, in the *frequency domain* (y-axis), there are 12*6=72 subcarriers, and hence 72 resource elements. there are 84 resrouce elements, as there are 7 symbols (x-axis), so 12*7 = 84.
dear sir can you Explain what is mode 3 and mode 6 which is use in pci planning please want to clear it but from the long time no one can able to clear it please
Hi Reshma. An excellent explanation for the motivation behind these rules is in section 31.5 of the book LTE in bullets, 2nd edition. In short: - UE should not be able to simultaneously receive PCI values with equal (i) PCI mod 3 value or (ii) PC mod 6 value. - If PCI mod 3 rule is met => PCI mod 6 rule is also met. If operator cannot meet PCI mod 3 rule, then operator tries to meet PCI mod 6 rule. - Two reasons for PCI mod 3 rule, both for deployments when eNBs are synchronized (typically TDD). (a) PSS are of three kinds; they point to the PCI Group (0,1 and 2). If UE receives two cells with the same PSS, it takes longer for UE to synchronize. Equal PCI mod 3 is equivalent to using the same PSS. (b) DL Cell specific reference signals for 2X2 and 4X4 MIMO are transmitted on the same subcarriers for cells with same PCI mod 3 value. CQI (cell quality indicator) reporting from UE gets adversely impacted in this case. - Reason for PCI mod 6 rule, again for deployment where eNBs are synchronized (typically TDD). If single antenna transmission is used, then DL cell specific reference signal are transmitted on the same subcarriers for cells with same PCI mod 6 value. The video above depicts this case. You can see that there are two subcarriers that carry the Reference Signal (red) are separated by 5 subcarriers in frequency domain. Each PCI++ shifts the RS subcarriers up by 1. For PCI and PCI+6, the RS subcarriers are the same. Again UE reporting of CQI value gets adversely impacted in this case.
Irfan Ali is indeed an excellent teacher, he is very knowledgeable and the pace of his delivery is very effective. I give him TWO THUMBS UP
Great tutorial on RSRP vs. RSRQ! Now it is clear why both measurement types exist!
You are welcome Bengi. I remember us (with Akin) struggling to figure out the details.
@@IrfanAli-nz7mb Thanks for the video. However, why did you divide RSSI by N_RB ? From the fact that max RSRQ is -3db it seems that RSSI is the sum of the total power in all the N_RBs, not per RE
Useful video. Thanks
Great explanation, thanks
I love ur training's. What is the main difference between RSRQ and SINR? From my understanding, RSRQ includes own cell load and SINR not but theoretically there is a calculation relation between SINR using RSRQ. That's where I confuse :) if rsrq is used in sinr calculation than own cell load does count. Where am I wrong ? Hope I am clear to explain :) Regards
Good tutorial.
Hi Irfan, if one RB has 4 ref signals then one ref signal should contain 25% of total energy, am I correct? But you are quoting 50%? Can you please clarify?
RSRQ measured per symbols not RB so it only have 2 RS and that will be 50% of energy
When rsrp and rssi both measure power in RS. What is the difference between them?
Dear Sir,
As we known, one of difference between RSRP and RSSI is the different measurement bandwidth.
RSSI is measured by full bandwidth with all RBs (1RB contains 12 REs) and RSRP is averaged power by one RE.
If noise/interference is added in the full bandwidth of all RBs, why the RE that contained RS not included the power of noise/interference?
Hi Jye, not sure i understand your question. imu, the energy in the reference symbol is also included in RSSI.
Dear Sir,
Thanks and understood that RSSI also contained the energy in the reference symbol.
Around 3:00, mentioned that "RSRP measures only the RS power and excluded all noise and interference power."
Just wondered how RSRP can exclude all noise and interference in detailed?
1 Resource block have 12 subcarriers 7 symbols and 84 resource elements right? if there are 6 PRB's then why resource elements are 72? I know right there are 72 RE in 6 PRB's but I want to know how? I'm confused somewhere.
Each PRB has 12 subcarriers. So, in the *frequency domain* (y-axis), there are 12*6=72 subcarriers, and hence 72 resource elements. there are 84 resrouce elements, as there are 7 symbols (x-axis), so 12*7 = 84.
@@IrfanAli-nz7mb Thank you so much !!
The minimum value of RSRQ is -3dB. The concept is clear. Could u pls explain on the maximum RSRQ ? How we get -19.5db ?
can you please explain about RSRP saturation and the reason why RSRP saturates?
Why there are 2 rs in one symbol.
dear sir can you Explain what is mode 3 and mode 6 which is use in pci planning please
want to clear it but from the long time no one can able to clear it please
Hi Reshma. An excellent explanation for the motivation behind these rules is in section 31.5 of the book LTE in bullets, 2nd edition. In short:
- UE should not be able to simultaneously receive PCI values with equal (i) PCI mod 3 value or (ii) PC mod 6 value.
- If PCI mod 3 rule is met => PCI mod 6 rule is also met. If operator cannot meet PCI mod 3 rule, then operator tries to meet PCI mod 6 rule.
- Two reasons for PCI mod 3 rule, both for deployments when eNBs are synchronized (typically TDD). (a) PSS are of three kinds; they point to the PCI Group (0,1 and 2). If UE receives two cells with the same PSS, it takes longer for UE to synchronize. Equal PCI mod 3 is equivalent to using the same PSS. (b) DL Cell specific reference signals for 2X2 and 4X4 MIMO are transmitted on the same subcarriers for cells with same PCI mod 3 value. CQI (cell quality indicator) reporting from UE gets adversely impacted in this case.
- Reason for PCI mod 6 rule, again for deployment where eNBs are synchronized (typically TDD). If single antenna transmission is used, then DL cell specific reference signal are transmitted on the same subcarriers for cells with same PCI mod 6 value. The video above depicts this case. You can see that there are two subcarriers that carry the Reference Signal (red) are separated by 5 subcarriers in frequency domain. Each PCI++ shifts the RS subcarriers up by 1. For PCI and PCI+6, the RS subcarriers are the same. Again UE reporting of CQI value gets adversely impacted in this case.
ourtechplanet.com/pci-planning-facts-myths/
Very poor clarification.
Speak loudly in next video