Carrier aggregation in LTE

Much advancement in Long Term Evolution (LTE) has been made as per 3GPP release papers. Release 8/9 terminals were not capable of providing greater data speed and hence did not meet the International Mobile Telecommunications - Advanced (IMT A) requirements. Therefore, there was need to increase the downlink and uplink data speed. Release 10 introduced a new feature in LTE called carrier aggregation in which different component carriers are aggregated in order to increase the overall bandwidth. In LTE-Advance, upto five component carriers can be aggregated but commercial solutions use up to three component carriers thus providing a maximum downlink speed of upto 450Mbps. This paper provides an overview of carrier aggregation and its needs. For cell edge users, carrier aggregation can be supported by enabling cross carrier scheduling which solves the problem of Inter Cell Interference. Carrier scheduling is enabled by eNodeb (eNB). In the later part of this paper, a simulation is discussed which provides understanding of calculation of various frequency parameters which are specified by 3GPP and also shows the plot of intra-band contiguous carrier aggregation which is commonly used.