Minimal Noise Variance Decoder for Uncoordinated Multiple Access in VLC

  • Abdullah A Saed
  • Chen C.
  • Jean-Marie Gorce
  • Siu-Wai Ho

This paper proposes an uncoordinated multiple access scheme for visible light communications (VLC) with positioning capability. The sinusoidal-based codes, proposed only for visible light positioning systems, are generalized in this paper by using a novel decoder design. The proposed scheme does not need a central unit to coordinate the transmission ...

power saving mechanism for contention-based M2M transmission

  • Wang H.
  • Yang L.

Massive number of devices must operate for a long time with very limited chance to contact energy sources in current Machine-to-Machine (M2M) networks, so power saving mechanism is very essential. In this paper, we analyze energy efficiency of two popular contention based data transmission methods (FSA and CTA) and proposed ...

Massive MIMO in Line-of-Sight Propagation

  • Marzetta T.
  • Yang H.

By calculating the effective max-min SINR (signal-to-interference-plus-noise ratio) and the corresponding power controls explicitly, and selectively dropping a small number of mobiles based on a simple and effective algorithm, we demonstrate that for both downlink and uplink, employing maximum-ratio or zero-forcing linear pre-coding and de-coding, Massive MIMO with max-min power ...

Unique Word DFT-Spread-OFDM for Fast Time-Varying Channels

  • Berardinelli G.
  • Frederiksen F.
  • Mogensen P.
  • Pedersen K.
  • Sorensen T.

Unique Word Discrete Fourier Transform -spread - Orthogonal Frequency Division Multiplexing (UW DFT-s-OFDM) waveform replaces the Cyclic Prefix (CP) with a known sequence which is contained in the symbol itself rather than being appended to it. In this paper, we propose a new UW DFT-s-OFDM design which aims at exploiting ...

Coverage Comparison of GPRS, NB-IoT, LoRa, and SigFox in a 7800 km² Area

  • Kovacs I.
  • Lauridsen M.
  • Mogensen P.
  • Nguyen H.
  • Sorensen M.
  • Vejlgaard B.

In this simulation work the coverage of GPRS, Narrowband-IoT, LoRa, and SigFox is compared in a realistic scenario, covering 7800 km2 and using Telenor's commercial 2G, 3G, and 4G deployment. The target is to evaluate which of the four technologies provides the best coverage for Internet of Things devices, which ...

Towards Zero Data Interruption Time with Enhanced Synchronous Handover

  • Gimenez L.
  • Kolding T.
  • Michaelsen P.
  • Nguyen H.
  • Pedersen K.

This paper presents enhancements for lowering the handover interruption time in future wireless networks. We propose a selective data forwarding for the handover preparation phase, and the integration of the make-before-break procedure with the synchronous random access-less handover. To evaluate our proposals, we analyze the handover timing for typical and ...

Indoor Deployment Strategies for Ultra Dense Urban Areas

  • Kovacs I.
  • Mogensen P.
  • Nguyen H.
  • Tavares F.
  • Wigard J.

Indoor deployments for providing coverage and capacity inside buildings is an attractive option for cellular network operators as most of the traffic in today's cellular networks is generated indoors. This paper studies the benefit of indoor traffic offloading on the overall network capacity using a new method that allows assessing ...

C/U Split Multi-Connectivity in the Next Generation New Radio System

  • Chen J.
  • Chen Z.
  • Chi J.
  • Du L.
  • Liu G.
  • Liu X.
  • Liu Y.
  • Qian X.
  • Yu T.
  • Zhao Z.
  • Zheng N.
  • Zhou H.

The next generation mobile network is foreseen as a heterogeneous network comprising not only the evolved existing systems but also the new radio (NR) spanning over the whole spectrum. Multi-connectivity (MC), where a UE aggregates the radio resources from multiple cells, provides an efficient way to fulfill the diverse 5G ...

Coverage and Capacity Analysis of Sigfox, LoRa, GPRS, and NB-IoT

  • Kovacs I.
  • Lauridsen M.
  • Mogensen P.
  • Nguyen H.
  • Sorensen M.
  • Vejlgaard B.

In this paper the coverage and capacity of SigFox, LoRa, GPRS, and NB-IoT is compared using a real site deployment covering 8000 km2 in Northern Denmark. Using the existing Telenor cellular site grid it is shown that the four technologies have more than 99 % outdoor coverage, while GPRS is ...

HOSVD-Based Denoising for Improved Channel Prediction of Weak Massive MIMO Channels

  • Amin M.
  • Haardt M.
  • Zirwas W.

Future mobile radio systems, like 5G, are setting extremely demanding targets with respect to the number of served users, data rates, and latency etc. Advanced techniques such as massive MIMO and joint cooperation over several distributed radio stations are being developed to achieve these targets. Channel prediction has been deemed ...

Pathloss Measurements and Modeling for UAVs Connected to Cellular Networks

  • Amorim R.
  • Kovacs I.
  • Mogensen P.
  • Sorensen T.
  • Wigard J.

This paper analyzes the radio channel between cellular network and Unmanned Aerial Vehichles (UAVs). The assessment is done by means of field measurements performed in a rural environment in Denmark. The tests were conducted in an operating LTE network (800 MHz), using a commercial cell phone placed inside the frame ...

Energy Efficient Coordinated Self-Backhauling for Ultra-Dense 5G Networks

  • Maeder A.
  • Prasad A.
  • Uusitalo M.

In recent past, the exponential growth in data rate demands have led to network operators constantly upgrading their network infrastructure in order to keep up with the demand. While the trends for data rate requirements are expected to continue in the future, mobile networks as part of evolution towards fifth ...

Big Data Analytics for 4.9G and 5G Mobile Network Optimization

  • Chiu P.
  • Holma H.
  • Luostari R.
  • Reunanen J.

Smartphones and other devices connected to a mobile network typically create billions of measurement samples every day. Those measurements are currently used for instantaneous resource allocation and link adaptation. There is much room for using the measurements also for network optimization with big data analytics. The measurements give valuable insight ...

Multi-Cell Performance of Grant-Free and Non-Orthogonal Multiple Access

  • Abebe A.
  • Kang C.
  • Lee J.
  • Rim M.

The compressive sensing-based random access may get impacted largely by other cell interference (OCI), which may shatter the sparsity of the received signal model unless the signature space assignment among interfering cells is carefully handled. In this paper, we investigate the performance of multi-sequence spreading-based random access (MSRA) scheme under ...

Evaluation of Indoor Radio Deployment Options in High-Rise Building

  • Kovacs I.
  • Mogensen P.
  • Nguyen H.
  • Tavares F.
  • Wigard J.

In this paper we set out to analyze the indoor capacity under a realistic high-rise building scenario. The study takes into consideration the number of indoor cells deployed per floor, different inter-site distances (ISDs), transmit power settings and outdoor macro interference levels. The outcome shows large variation in performance gain ...

Compact undersampled digital predistortion for flexible single-chain multi-band RF transmitter

  • Farrell R.
  • Guan L.
  • Wang Z.

Compact multi-band RF transmitter solution will play a unique role in the forthcoming 4G-beyond and 5G wireless networks. The emerging RF class data convertor, i.e., RFDAC enables a promising single-chain multi-band RF transmitter solution. To combat the imperfections of practical nonlinear power amplifiers in the single-chain multi-band RF solution, we ...

Silicon photonics enabled hyper-wideband wireless communication link

  • Chang C.
  • Chen Y.
  • Chimot N.
  • De Valicourt G.
  • Dong P.
  • Eggleston M.
  • Itoh T.
  • Kaneda N.
  • Kim K.
  • Lelarge F.
  • Sinsky J.
  • Wu M.

We demonstrate the first silicon photonics enabled hyper-wideband wireless link with an instantaneous bandwidth of 12 GHz, which is 85% of the center frequency of 14 GHz. The silicon photonics based RF receiver consists of a four-channel optical phase encoder, an integrated hybrid-silicon mode-locked laser, and two silicon ring notch ...

An 80MHz modulation bandwidth high efficiency multi-band envelope-tracking power amplifier using GaN single-phase buck-converter

  • Asbeck P.
  • Fujiwara T.
  • Kolmonen T.
  • Lanfranco S.
  • Piirainen O.
  • Sakata S.
  • Shinjo S.

We report a high efficiency multi-band Envelope-Tracking Power Amplifier (ET-PA) that supports modulation bandwidth up to 80MHz using real-time digital predistortion (RT-DPD). The ET-PA consists of a broadband RF-PA and a singlephase buck-converter. The RF-PA has maximum PAE over 50% from 0.7 to 2.1GHz in CW measurements. The buck-converter operates ...

On the Design of Preamble for Autonomous Communications with Extended Coverage

  • Balachandran K.
  • Kang J.
  • Karakayali K.
  • Kocak M.
  • Rege K.

5G wireless networks are expected to usher in massive Machine Type Communications (mMTC) pertaining to the Internet of Things (IoT). A large fraction of the devices participating in IoT are likely to be low-power devices that generate sporadic traffic. It is anticipated that autonomous grant-free communications would be needed to ...

Coexistence of 5G With the Incumbents in the 28 and 70 GHz Bands

  • Bechta K.
  • Dietrich C.
  • Ghosh A.
  • Kim S.
  • Moorut P.
  • Visotsky E.

A promising way of realizing the fifth generation (5G) wireless systems is to operate 5G deployments at higher frequency bands, specifically in the millimeter-wave (mmW) spectrum (30â?"300 GHz). Access to such spectrum bands will enable future 5G wireless systems to meet the 5G requirements of peak rate greater than 10 ...