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Showing posts from December, 2013

Co-ordinated Multi point transmission and reception- 3GPP Rel 11

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The main reason to introduce CoMP is to improve network performance at cell edges. In CoMP a number of TX (transmit) points provide coordinated transmission in the DL, and a number of RX (receive) points provide coordinated reception in the UL.  TX/RX-point A TX/RX-point constitutes of a set of co-located TX/RX antennas providing coverage in the same sector.  The set of TX/RX-points used in CoMP can either be at different locations, or co-sited but providing coverage in different sectors, they can also belong to the same or different eNBs. CoMP can be done in a number of ways, and the coordination can be done for both homogenous networks as well as heterogeneous networks.  In figure 8 two simplified examples for DL CoMP is shown. In both these cases DL data is available for transmission from two TX-points.  Joint Transmission When two, or more, TX-points, transmit on the same frequency in the same subframe it is called Joint Transmission . Dynamic Point Sele

LTE Advanced in unlicensed spectrum

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 For operators to meet the anticipated 1000x increase in data traffic, deploying more small cells and utilizing all spectrum resources are key. Although licensed spectrum is the foundation, bandwidth-rich unlicensed spectrum around 5 GHz band can be used to effectively augment the capacity. The question is how to best opportunistically utilize it. Extending the benefits of LTE Advanced to unlicensed spectrum brings its basic tenets of high-efficiency and robust mobility, while also making it a seamless extension of the larger LTE Advanced network. That means higher performance for operators and better broadband experience for users, and a common unified network for all spectrum types. Enhanced user experience Since a unified network with common core and integrated small cells offers the same LTE Advanced service on both licensed and unlicensed spectrum, users get the most seamless mobility between the two. Additionally, carrier