hybrid beamforming for 5g system level modeling
TRANSCRIPT
1 © 2019 The MathWorks, Inc.
Hybrid Beamforming for 5G
System Level Modeling
Gerald Albertini
November 08th 2019
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System Level Modeling / team collaboration
Baseband Digital
Front End DAC PA
LNA ADC Baseband Digital
Front End
Digital PHY RF Front End
Antenna
TRANSMITTER
RECEIVER
Channel
RF Design DSP Algorithms
Software
Development System
Architecture
Digital
Hardware
Mixed-Signal
Hardware
Antenna
Design
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BB Modeling : Support Latest Standards
5G Toolbox: A new product for simulating, analyzing,
and testing the physical layer of 5G communication
systems
IEEE 802.11ax and 802.11ad are new Wi-Fi standards
intended for high data rate communications
NB-IoT and LTE-M are machine-to-machine (M2M)
applications for the Internet-of-Things (IoT)
D2D and C-V2X are LTE application for device-to-device
and cellular vehicular communications
Simulate, analyze and test 5G radio links. Generate
IEEE 802.11ax/ad and LTE NB-IoT, LTE-M, D2D, and C-
V2X compliant waveforms
LTE Toolbox™
+
+
5G Toolbox™
+ WLAN Toolbox™
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Easily and graphically configure,
generate, visualize and export wireless
waveforms. Connect and transmit
waveforms on RF instruments
Supported waveforms
– WLAN: (IEEE 802.11a/b/g/j/p/n/ac/ah/ad/ax)
– LTE: (Uplink & Downlink RMC and E-TM)
– Custom-modulations: (QAM / PSK / OFDM)
RF instrument connectivity (e.g., Agilent,
Rohde & Schwarz)
– Automatically discover available instruments
– Transmit/stop infinitely looped waveforms
Ease of use : Wireless Waveform Generator App
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Antenna Array Modeling
Design subarrays
Synthesize arrays Model mutual coupling Model imperfections
Design/import antenna
patterns
Design an array
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Building an Array Using Subarrays
Replicate to build array
Assess resulting pattern
Design subarray with desired fidelity
or
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Channel Models
• LOS propagation channel
• Multiple-ray propagation channel
• 5G channel model
• Scattering MIMO channel
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1>> All Digital : MIMO-OFDM Precoding Example
Beamforming where each transmit/receive element is controlled with amplitude and
phase
Baseband
precoding
DAC RF
… NT
…
DAC RF
Baseband
combining
ADC RF
… NR
…
ADC RF
https://www.mathworks.com/help/comm/examples/mimo-ofdm-precoding-with-phased-arrays.html
Single-user MIMO-OFDM system
Up to 16 data streams
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2>> Introduction to Hybrid Beamforming
Beamforming done in two stages:
– RF Beamforming
– Digital Beamforming
Baseband
R
F
R
F
R
F
R
F
H Baseband
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Constraints in Hybrid Beamforming
Partitioning is an optimization problem with constraints
Magnitude and phase flexibility (vs. analog only phase shifter)
Power limits
Phase shifter finite resolution
Phase shifter bandwidth performance
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Pattern and Spectrum Efficiency Comparisons
Beampattern with hybrid weights (discrete hybrid beamforming)
Beampattern for optimal precoding weights (all digital)
Spectrum Efficiencies of Optimal Weights and Discrete Weights
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Hybrid Beamforming with Sparse Beamspace Precoding
Need only as many RF chains as number of Tx data streams (𝑁𝑆)
Number of transmit antennas >> 𝑁𝑆 (𝑁𝑅𝐹), with appropriate RF beamforming
Map each RF chain to each Tx
element
Map each RF chain to only a subset
of Tx elements (subarrays) Virtual sectors (MU case)
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Closed loop simulation - Simulink
System level modeling
Multidomain (baseband, RF modeling)
Closed look (feedback)
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Summary
Antenna, RF design & signal processing development in single environment
Modelling can help to define architectures for hybrid beamforming
The hybrid beamforming algorithm well suits for limited feedback systems
The hybrid beamforming algorithm can approach the theoretical limits on spectral efficiency