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Internship Program in Radio Access Systems Laboratory in TCU

Internship Program in Radio Access Systems Laboratory in TCU

2015.06.05 Prof. M. Sawahashi

Department of Information and Communication Engineering, Tokyo City University

2015.06.05 Prof. M. Sawahashi

Department of Information and Communication Engineering, Tokyo City University

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Prof. M. Sawahashi• He was engaged in research and development of radio access

techniques for 3G WCDMA and 4G LTE/LTE-Advanced in NTT DOCOMO INC.

• His received National Invention and Innovation Award by the Prime Minister, Japan, by the WCDMA patent in 2010 and National Invention and Innovation Award the Commissioner of Patents by the LTE patent in 2015.

• He published more than 140 journal papers including IEICE and IEEE papers and more than 230 international conference papers with reviews.

Radio Access Systems Laboratory in TCU• 7 undergraduate students• 8 graduate students

7 master course students 1 doctor course student

Radio Access Systems Laboratory

History of Radio Access for Cellular Systems

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2G 3G 4G

GSMPDC

D-AMPS

W-CDMACDMA2000

TDMA CDMA

HSDPA/HSUPA

LTEWiMAX

LTE-AdvancedIEEE802.16m

OFDMASC-FDMA

(N)OFDMA(N) SC-FDMA

3.0G 3.5G 3.9G 4.0G

Circuit-switched based access

(Dedicated channels) Packet based access(Shared channels)

• Digital cellular systems

• High capacity for voice traffic channel

• Multi-rate transmission

CDMA(Code-multiplexing)

• High throughput for data traffic

• Low latency

• Higher frequency efficiency and higher peak data rate

• Low latency

Difference of used frequency spectra

Difference of radio access schemes 5G

New Multi-access

schemes and

Radio access

techniques

Research area in our Lab.

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We need radio access technologies that satisfy future requirement on capacity of 500 – 1000 times.

• New radio accedes techniques to further improve frequency efficiency

• Spectrum extension

• Improvement of network density - Smaller cell deployment including pico cell and femto

cell- Heterogeneous networks

• Traffic offload

- WiFi offload

- D2D (Device-to-device) communication

Approaches of 5G Radio Access Techniques

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Multi-Access: Non-orthogonal multi-access schemes• Faster-than-Nyquist (FTN) and partial response (PR)

transmission• Higher multi-level modulation such as 128, 256, 512QAM

Efficient multiplexing schemes for control signals Cell search for heterogeneous networks Interference canceller: Turbo SIC, MLD, LMMSE Enhance channel estimation:

• Iterative decision-directed channel estimation (IDDCE) Higher-order MIMO multiplexing

• Throughput evaluation of MIMO beyond 8 antennas• Signal detection schemes: turbo SIC, MLD, LMMSE

Adaptive rate control (AMC) for MIMO multiplexing Transmit diversity with greater than 4 antennas

Major Research Topics in the Laboratory

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Internship period: On and after August 24, 2015. Decide a research topic after discussing with Prof.

Sawahashi Training• Study the technical background of the research• Computer simulations• Report for the research

Optional event: Visit NTT DOCOMO Research Center for instance.

Internship Program