Bug 2821

Summary: Incorrect limit for UL retransmissions in Round Robin Scheduler
Product: ns-3 Reporter: Zoraze Ali <zorazeali>
Component: lteAssignee: Biljana Bojović <bbojovic>
Status: RESOLVED FIXED    
Severity: normal CC: ns-bugs
Priority: P3    
Version: ns-3-dev   
Hardware: All   
OS: All   
Attachments: Uplink Rx stats
test script
RrFfMacScheduler patch
Uplink Rx stats correct

Description Zoraze Ali 2017-11-14 06:20:01 UTC 
Created attachment 2955 [details]
Uplink Rx stats

Hi, 

The condition to limit the uplink retransmission in Round Robin scheduler is not correct. Currently, it is "if ((*itStat).second.at (harqId) > 3)", we should change it to "if ((*itStat).second.at (harqId) >= 3)" to limit the retxs till redundancy version number 3. 

I am attaching UlRxPhyStats to see the incorrect behaviour in which RV number go beyond 3.

These results are generated after applying the patches for Bug#2151 and Bug#2152

https://www.nsnam.org/bugzilla/﷒0﷓

https://www.nsnam.org/bugzilla/﷒1﷓
Comment 1 Zoraze Ali 2017-11-14 06:23:23 UTC 
Created attachment 2956 [details]
test script
Comment 2 Zoraze Ali 2017-11-14 06:23:41 UTC 
To run the test, it is also necessary to modify the lte-spectrum-phy.cc to force packet corruption by modifying the function EndRxData at line 972 to:
 (*itTb).second.corrupt = true;

By calling the script as follows
./waf --run "harq-test --interPacketInterval=9 --maxPackets=2"
Comment 3 Zoraze Ali 2017-11-14 06:31:02 UTC 
Kindly disregard the last comment on running the test script. Following is the updated info. 

To run the test, it is also necessary to modify the lte-spectrum-phy.cc to force packet corruption by modifying the function EndRxData at line 995 to:
 (*itTb).second.corrupt = true;

By calling the script as follows
./waf --run "rr-test --maxPackets=2"
Comment 4 Zoraze Ali 2017-11-14 06:33:31 UTC 
Created attachment 2957 [details]
RrFfMacScheduler patch
Comment 5 Zoraze Ali 2017-11-14 08:54:02 UTC 
Created attachment 2958 [details]
Uplink Rx stats correct

The abnormal behaviour can be noticed at 140 msec.
Comment 6 Biljana Bojović 2017-11-17 06:04:36 UTC 
Pushed to changeset 13178:68035954e07c.