lte-a data throughputs in realistic macro and pico cellular environments

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Impact of BS Antenna Number and Array Geometryon Single-User LTE-A Data Throughputs in RealisticMacro and Pico Cellular EnvironmentsPresentation for WCNC2015March 10, 2015

Siming Zhang, Di Kong, Evangelos Mellios, Geoffrey Hilton and Andrew NixCommunication Systems & Networks GroupUniversity of Bristol, United KingdomTimothy A. Thomas, Amitava GhoshNokia NetworksArlington Heights, IL60004, US

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Presentation OutlineRationale and 3D Extension of 3GPP/ITU Channel Model3D Ray-tracing and Simulation ConfigurationsSU-MIMO LTE-A PHY Abstraction Engine Results and DiscussionsConclusions and Future Work

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Communication Systems & Networks CSN Group 2015

Communication Systems & Networks CSN Group 20153D Extension of the 3GPP/ITU Channel Model3Our Motivations: Recently there have been proposals to extend MIMO processing to the elevation direction. To accurately assess the promised gains of these 3D-MIMO techniques and Massive MIMO, a channel model is needed.3D Ray-Tracing (Prophecy)

We Proposed: An extension of the ITU 2D channel model to 3D by adding a distance dependent elevation spread based on observations from City-Scale 3D Ray-Tracing in Urban Macrocells and Picocells: London city-centre (143 km2)Bristol city-centre (17.6 km2)Two types of environments considered per city: 23 macro BS and 600 pico BS



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Typical Basestation and Mobile Antenna ConfigurationsMeasured Basestation and Mobile Antenna Patterns

3D-SU-MIMO LTE-A Channel and Antenna Models

123456789108x80.5 vert8x80.5 mix8x80.5 hori8x82vert8x82mix8x82 hori12x80.5 mix12x80.5 hori16x80.5 mix16x80.5 hori

3D Ray-Tracing (Prophecy)

Macro/Pico Cell BS UE

500,000 link evaluations!!



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LTE PHY Abstraction Simulator5

Received Bit Mutual Information Rate (RBIR) simplifies link to system level simulation. H(n,m,l,t) represents the frequency response of subcarrier l for the link from transmit antenna m to receive antenna n at channel snapshot t, where Nf represents noise floor at the receiver. Then UE-specific PERi,j of MCS mode i when running j parallel streams was mapped and used for calculating the achievable Throughput :where Ri,j represents the peak error free data rate for a given MCS mode with j streams. For instance, the peak rate for 8-stream operation using 64QAM 3/4 rate code is 302.4 Mbps.



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Probability of supporting k-spatial streams Throughput StatisticsSpatial Streams vs SNR (LoS vs NLoS)6



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73D-SU-MIMO LTE-A Capacity Study

A 16x8 offers 35% more capacity than an 8x8 system. This relative gain held true for both Macro and Pico cells.



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8For Macro cell deployments, a high BS antenna number results in a poor return on investment in terms of capacity, but in terms of QoS a significant reduction in the outage probability of cell edge users is observed.

For Pico cells the capacity results for large BS arrays are more encouraging, and impressive outage improvements were also reported.

Users are unlikely to experience the peak rates quoted for the hardware, importance of real-world evaluations, simple channel model over-predict the potential capacity.

On-going work involves MU-MIMO in LTE-A and 5G Massive MIMO simulations and Testbed!Conclusions and On-going Research



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Thank you !

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lte-a data throughputs in realistic macro and pico cellular environments

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