LTE Multiple Antenna Techniques

LTE Multiple Antenna Techniques

This course provides a thorough description of the contemporary and future multiple antenna systems, particularly concentrating on MIMO (Multiple Input Multiple Output) techniques applied in the context of the 3GPP-LTE standards. We start by providing a refreshment of the wireless propagation and antenna theory and reviewing various types of diversity techniques. This is followed by the discussion of SU-MIMO (Single-User MIMO) schemes, beamforming and MU-MIMO (Multi-User MIMO) methods. Techniques such as SDMA (Space Division Multiple Access), multi-dimensional scheduling and combination of MIMO with OFDM/OFDMA are explained. Subsequently, the context of multi-antenna usage in LTE is described in detail, including its possible options, limitations, practical considerations, and influence on the system performance. The course is ended by the presentation of the multiple antenna usage in the context of other wireless systems, including eHSPA and WiMAX.

This theoretical course, utilizing renowned DTM methodology, will be enriched by providing the real demonstrations of the MIMO operation based on the interactive tool implementing the processing blocks of the eNB.

Note: The course content is subject to changes.

Introduction to antenna theory

• Multipath propagation
• Isotropic and dipol antennas
• Electromagnetic wave polarization, beam patterns
• Antenna parameters (gain: dBi, dBd, HBW, front-to-back ratio, EIRP, sidelobe level)
• Fresnel zone

Diversity techniques

• Diversity in time, frequency and space
• Basic diversity methods including switched/selection diversity; equal gain, maximal ratio and Alamouti combining
• RAKE receiver
• Cyclic delay diversity
• Space-Time Block Coding, Space-Time Trellis Coding

Beamforming and array processing

• Principles of beamforming
• Direction of Arrival (DoA), Direction of Departure (DoD)
• Beamforming at the transmitter vs beamforming at the receiver
• Eigenbeam beamforming
• Multi-user beamforming
• Practical aspects of beamforming

Single-user MIMO

• Principles of spatial multiplexing (spectral efficiency and capacity, transmitting independent streams in parallel)
• Open loop vs closed loop spatial multiplexing
• Open loop encoders and decoders (horizontal, vertical, diagonal)
• Singular value decomposition and MIMO channel in closed loop spatial multiplexing
• Power allocation and waterfilling concepts

Multi-user MIMO

• The concept and possible types of multi-user MIMO (downlink, uplink, single-cell, multi-cell)
• Combination of OFDMA with MU-MIMO
• MU-MIMO scheduling, rate and link adaptation
• Uplink collaborative MIMO
• Downlink beamforming and SDMA
• Multi-cell MU-MIMO and distributed antennas

LTE Multi-antenna Details

• MIMO processing when combined with OFDMA and SC-FDMA
• Multi-antenna combinations possible in E-UTRA Rel 8
• LTE MIMO processing chain at the transmitter and at the receiver, pilot patterns
• Options for transport block, codeword, layer and antenna mapping
• SFBC, SM and beamforming MIMO realizations in LTE
• MIMO mode switching (including switching between SU-MIMO and MU-MIMO)
• MIMO feedback (Pre-coding Matrix Indicator and Rank Indicator)
• Rel 10 LTE MIMO extensions

LTE Multi-antenna Practical Considerations

• Demonstrations of the MIMO operation based on the interactive tool implementing the processing blocks of eNB
• Practical use cases of LTE MIMO
• Typical antenna configurations in commercial cellular deployment
• Influence of MIMO application on the LTE network performance (improvement of robustness, capacity, range but also the price to be paid)

Multiple antennas in other wireless systems

• Multi-antennas in eHSPA
• Multi-antennas in mobile WiMAX

The LTE Multiple Antenna Techniques training course is developed for all telecom professionals working with implementation, planning and deployment of the LTE multiple antenna systems. The course is also suitable for technical decision makers, project managers, researchers, as well as test and verification engineers seeking to broaden their LTE expertise in the area of multi-antenna application.