GSOC2015LTECA

Carrier Aggregation support for the LTE module

Student: Danilo Abrignani

Mentors: Marco Miozzo Nicola Baldo

• Abstract: 3GPP standardizes, in release R10, the Carrier Aggregation (CA) technology. This consists of the possibility, for a single user equipment (UE), to aggregate Radio Resources belonging to different carriers, in order to have more bandwidth available, and a higher potential throughput. The idea is to improve the current LENA implementation, with CA functionalities, by implementing a sort of “proxy” between the RLC/RRC layer and MAC/Scheduler layers, associated to the multiple carriers.
• Code: http://code.nsnam.org/daniloa/ns-3-dev-lte-ca/
• About me: I'm a Ph.D. candidate at the University of Bologna, Italy. My research interests are in wireless sensor network and mobile network simulation. Something more about me on my Linkedin page.

Plan

• 1st Week:

 * Implementation of RRC messages for Carrier Aggregation support
 * Writing design documentation 

• 2nd - 4th Weeks:

 * Implementation of the LTE-A helper, activation of different carriers and synchronization procedure. 
 * Writing test code and debugging.
 * Writing design documentation

• 5th - 6th Weeks:

 * Write test documentation, submit code for review, consolidate code and documentation. 

• 7th -8th Weeks:

 * Start writing the CA-Mac module, design documentation.
 * Write test and debugging, writing test documentation, submit code for review.

• 9th - 10th Weeks:"'

 * Define a basic algorithm that takes into account QoS indicators. Write design documentation
 * Writing test application and debugging. Submit code for review. Update code and documentation.

• 11th - 12th Weeks:

 * Unified LTE-A and LTE helpers. 
 * Write test applications, update documentation and code. 
 * Possible improvements.

Weekly Progress

Week 1 (May 25, 2015 - May 31, 2015)

First week of coding phase has delivered the following:

• Implementation of RRC messages for Carrier Aggregation support
• Implementation of CcsAlgorithm abstract class which will be base class for Carrier Component Selection (CCS) algorithms
• Implementation of SAPs
• LteHelper was updated to install CCS entity and SAPs during setting up EnbNetDevice. However, currently no ccs algorithm is implementing.

• 

  Carrier Aggregation Configuration - Messages Exchange

• 

  Carrier Component Selection Module

Week 2 (June 01, 2015 - June 07, 2015)

In summary, this week I delivered the following:

• Minor error fix on RRC SAP

• ASN1 - RRC coding implemented:
  • Basically I implemented the serialize and deserialize method for coding the new fields in the rrcConfigurationReconfiguration message.
  • Minor change in ASN1 Header, i.e. adding a function template in order to match a new bit mask, the latter it is used to enable or disable optional fields in RRC headers.

• Tested carriers aggregation CA enable procedure (messages exchange) when RrcIdeal is false.

Some References

• • LTE-A HetNets using Carrier Aggregation, Nomor whitepaper [1]
  • 3GPP TS 36.211
  • 3GPP TS 36.213
  • 3GPP TS 36.331