24-11-2012, 03:47 PM
RESOURCE ALLOCATION TECHNIQUES IN LTE
RESOURCE ALLOCATION.pptx (Size: 452.39 KB / Downloads: 22)
Abstract
This project attempts to explore Resource Allocation Techniques under Long Term Evolution (LTE) by implementing the algorithm using MATLAB. Various methods are focused on different aspects like, Quality of Service (QoS), varying SINR and requested data rate etc. Each of these methods aim to achieve lower Packet Data Ratio (PDR), and a better trade off between capacity and fairness.
Understanding LTELong Term Evolution
Features are:-
Next step forward in cellular 3G services
LTE is one of two parallel projects initiated by 3GPP i.e. Long Term Evolution (LTE) and System Architecture Evolution (SAE)
Uses Orthogonal Frequency Division Multiple Access(OFDMA) on the downlink (DL) and Single Carrier – Frequency Division Multiple Access (SC-FDMA) on the uplink (UL).
Problem Statement
To identify an efficient Scheduling Algorithm for LTE Cellular System, keeping in view:-
Users in an OFDMA system in LTE will experience different fading environments, and thus the SNR and received power variations will differ for each user.
Different Quality of Service (QoS) requirements, dictating the SNRs and received powers required at their receivers.
Total power constraints or requirements to minimize consumed power.
Wireless channels are subject to constant change in real life, so resource allocation techniques must be highly adaptive.
What is RB?
In LTE cellular system, subcarriers are grouped into resource blocks (RBs) of 12 adjacent subcarriers with an inter subcarrier spacing of 15 kHz. The smallest resource unit that a scheduler can assign to a user is a scheduling block (SB), which consists of two consecutive RBs, spanning a subframe time duration of 1 millisecond
Advantages
Easy to implement.
Thresholds for different users or traffics can be set.
One cell can reserve some RBs to support handover users or variable-rate users.
Spectrum efficiency and average cell throughput are maintained even in absence of handover process.
Conclusion
In this paper we have attempted to touch upon the existing approaches for equal power distribution in all sub channels, thus increasing the overall capacity of each channel.