# Modifying Prop Fair Scheduling Code on Vienna SL 1.9 Simulator

Viewing 3 posts - 1 through 3 (of 3 total)
• Author
Posts
• #9394
ahmetemir
Participant

Hello,

I’m new on Vienna Downlik System Levem Level Simulator 1.9 Q2-2016. I want to modify prop fair scheduling algorithm to implement generalized proportinal fair scheduling algorithm. First af all I want to understand propFairSunScheduler.m of original Vienna 1.9 SL project. I read LTE-A System Level Documentation v1.9 Q2-2016 documentation. According to this documentation , proportional fair scheduler has been written , as in paper ”Reduced-Complexity Proportional Fair Scheduling for OFDMA Systems” by Z. Sun, C. Yin, and G. Yue ( link:http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=4064107).

In this paper proposed algorithm has been given on secton IV proposed PF Scheduling Algortihm For OFDMA Systems by Step1 ,Step 2 and Step 3 equations. In propFairSunScheduler.m I saw below code on PF_Scheduler function :

`metric(res(1:sum(RB_set)),:) = cleaned_c_log_matrix(res(1:sum(RB_set)),:)+UE_avgd_pre_metric_mat(res(1:sum(RB_set)),:);`

Is this code calculate PF metric? I couldn’t find any correlation between this code and step1 on this document at this link:http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=4064107 . Where is the code part of Step1 ,Step2 and Step3 on original Vienna SL Simulator1.9.

Best Regards…

• This topic was modified 4 years, 4 months ago by ahmetemir.
• This topic was modified 4 years, 4 months ago by ahmetemir.
#9523
ahmetemir
Participant

While I’m trying to solve , in below code:

`metric(res(1:sum(RB_set)),:) = cleaned_c_log_matrix(res(1:sum(RB_set)),:)+UE_avgd_pre_metric_mat(res(1:sum(RB_set)),:);``

I realized that UE_ avd_pre_metric_ mat is calculated as:

`UE_avgd_pre_metric = -alpha_temp*log10(max(avgd_UE_throughputs+sum(RB_UEs.*c,1)*12*7,eps));`
`UE_avgd_pre_metric_mat = UE_avgd_pre_metric(ones(1,N_RB),:);`

Also I’m thinking UE_avgd_pre_metric is similar as Equation(11) in the document (link: http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=4064107) İs it true?

But I couldn’t understand to calculate PF metric why cleaned_c_log_matrix is added to UE_avgd_pre_metric ? What are cleaned_c_log_matrix and UE_avgd_pre_metric exactly?

Would you explain me please? I couldn’t understand this expression from code? In order to modify prop fair scheduling I have to understand Vienna1.9 codes in detail .

Best wishes..

• This reply was modified 4 years, 4 months ago by ahmetemir.
• This reply was modified 4 years, 4 months ago by ahmetemir.
• This reply was modified 4 years, 4 months ago by ahmetemir.
• This reply was modified 4 years, 4 months ago by ahmetemir.
• This reply was modified 4 years, 4 months ago by ahmetemir.
#9842

Dear ahmetemir,

Step 1 is represented by parameter metric, step 2 by maximizing the metric, and step 3 is represented by the loop over the number of resource blocks.

Since the implementation was done long time ago, by another member of our team, hard to say one-to-one which parameter presents which part of the equation. To give you an idea, the parameter c represents the rate r, nominator of equation (16), while avgd_UE_throughputs represents the term (t_c – 1)*T_k.

In order to speed up the calculation, a lot of precalculation is done and vector/matrix notation is used.

Best regards,
Fjolla

Viewing 3 posts - 1 through 3 (of 3 total)
• The forum ‘Vienna LTE-A Downlink System Level Simulator’ is closed to new topics and replies.