Thermal memory effect characterization of GaN based class ABJ power amplifier using intrinsic temperature measurement

Enhancing power efficiency and bandwidth of RF power amplifiers (PAs) is always a challenge for future mobile basestation transceivers. Static and especially dynamic nonlinear effects are mainly responsible for decreasing before mentioned parameters. Static effects can be usually characterized by measuring the PA output with a defined input signal. Fast ...

Viability analysis of content preparation configurations to deliver 360VR video via MPEG-DASH technology

We present a viability analysis of a content preparation scheme used to smartly distribute mono-and stereoscopic 360VR video using the MPEG-DASH paradigm. Several configurations in which the portion of the scene that is located at the opposite side of the viewport is set to black have been studied. The main ...

Scalable Monitoring of End-to-End Delay in Live Video Services

  • Lopez Poncela J.
  • Perez P.
  • Ruiz Alonso J.
  • Villegas A.

In this article, we propose a simple method to monitor the end-to-end live lag in a way which is scalable and meaningful for the service providers. The proposal is based on detecting the wall-clock timestamp of the video frames at capture time and inserting it in-band, so that it is ...

Linear Programming Bounds for Entanglement-Assisted Quantum Error-Correcting Codes by Split Weight Enumerators

  • Ashikhmin A.
  • Lai C.

Linear programming approaches have been applied to derive upper bounds on the size of classical and quantum codes. In this paper, we derive similar results for general quantum codes with entanglement assistance by considering a type of split weight enumerator. After deriving the MacWilliams identities for these enumerators, we are ...

138 Tbit/s Mode- and Wavelength Multiplexed Transmission over 6-Mode Graded-Index Fiber

  • Alvarado-Zacarias J.
  • Alvarez-Aguirre R.
  • Amezcua Correa R.
  • Chen H.
  • Fontaine N.
  • Gruner-Nielsen L.
  • Jensen R.
  • Koonen T.
  • Lingle R.
  • Okonkwo C.
  • Ryf R.
  • Sun Y.
  • Van Weerdenburg J.

We report on the multiplexing of 12 spatial channels and 120 wavelength channels in the C-band, each carrying 16-QAM symbols at 30 Gbaud over graded-index few-mode fiber. A combination of multiple fiber spools with positive and negative modal dispersion values are exploited to form a 59 km link with 0.35 ...

Kramers-Kronig Receivers for 100-km Datacenter Interconnects

  • Antonelli C.
  • Chen X.
  • Mecozzi A.
  • Raybon G.
  • Sethumadhavan C.
  • Shtaif M.
  • Winzer P.

In this paper, we review in detail experimental demonstrations of Kramers-Kronig (KK) based direct detection systems with high per-carrier interface rates, high spectral efficiencies, and ~100-km reach. Two realizations of KK based receivers are demonstrated, including single-polarization and dual-polarization versions. Critical aspects of the KK receiver such as the carrier-to-signal ...

Directly Reflectivity Modulated Laser

  • Brent R.
  • Chen Y.
  • Dong P.
  • Maho A.
  • Melikyan A.

We report a novel directly reflectivity modulated laser (DRML) whose output is modulated through a Michelson interferometer reflector of the laser cavity. 25/40 Gb/s on-off-keying and 25 Gb/s binary phase-shift keying signals are generated and the wavelength tunability is >20 nm.

Massive MIMO has Unlimited Capacity

  • Bjornson E.
  • Hoydis J.
  • Sanguinetti L.

The spectral efficiency (SE) of cellular networks can be improved by the unprecedented array gain and spatial multiplexing offered by Massive MIMO. Since its inception, the coherent interference caused by pilot contamination has been believed to create a finite SE limit, as the number of antennas goes to infinity. In ...

QoS-aware protection in flexgrid optical networks

Elastic optical networks generally rely on protection and restoration mechanisms to prevent the detrimental effect of fiber cuts. In particular, we investigate optical protection in flexgrid optical networks where the symbol rate is varied as a complementary approach to modulation format. We propose a novel protection scenario, whereby premium traffic ...

Finite-Length Analysis of Spatially-Coupled Regular LDPC Ensembles on Burst-Erasure Channels

Regular Spatially-Coupled LDPC (SC-LDPC) ensembles have gained significant interest since they were shown to universally achieve the capacity of binary memoryless channels under low-complexity belief-propagation decoding. In this work, we focus primarily on the performance of these ensembles over binary channels affected by bursts of erasures. We first develop an ...

Low-Complexity Nonlinear Zero-Forcing Precoding Under Per-Line Power Constraints for Improved Downstream Active-User Peak-Rates

We consider nonlinear zero-forcing (ZF) precoding design to improve the downstream peak-rates when only a few users in the cable binder are active. In order to compute the optimal nonlinear ZF precoder under per-line power constraints (PLPCs), we present a novel low-complexity dual decomposition algorithm, in which the key ...

Beamforming with Artificial Noise for Secure MISOME Cognitive Radio Transmissions

In this paper, we consider multiple-input singleoutput multi-eavesdropper (MISOME) cognitive radio networks (CRNs), where a secondary user (SU) aims to transmit confidential information to a legitimate SU receiver (SU-RX) in the presence of a primary user (PU) and a multi-antenna passive eavesdropper in fast fading environments. For this system setting, ...

How to ensure reliable connectivity for aerial vehicles over cellular networks

  • Amorim Rafhael
  • Kovacs I.
  • Mogensen P.
  • Nguyen H.
  • Sørensen Troels
  • Wigard J.

Widely deployed cellular networks are an attractive solution to provide large scale radio connectivity to unmanned aerial vehicles. One main prerequisite is that coexistence and optimal performance for both aerial and terrestrial users can be provided. Todays cellular networks are, however, not designed for aerial coverage, and deployments are primarily ...

Optimal VNFs placement in CDN Slicing over Multi-Cloud Environment

This paper introduces a Content Delivery Network as a Service (CDNaaS) platform that allows dynamic deployment and life-cycle management of virtual Content Delivery Network (CDN) slices running across multiple administrative cloud domains. The CDN slice consists of four Virtual Network Function (VNF) types, namely virtual transcoders, virtual streamers, virtual caches, ...

Coalitional Game for the Creation of Efficient Virtual Core Network Slices in 5G Mobile Systems

Many ongoing research activities relevant to 5G mobile systems concern the virtualization of the mobile core network, including the Evolved Packet Core (EPC) elements, aiming for system scalability, elasticity, flexibility, and cost-efficiency. Virtual EPC (vEPC)/5G Core will principally rely on some key technologies such as Network Function Virtualization (NFV), Software ...

Correction Factor for Analysis of MIMO Wireless Networks With Highly Directional Beamforming

In this letter, we reconsider a popular simplified received signal power model with single stream beamforming employed by the transmitter and the receiver in the regime when the beams have high gain and narrow beamwidth. We define the correction factor as the ratio of the average actual received signal power ...

Silicon Photonics Enabled Hyper-wideband RF Receiver With >85% Instantaneous Bandwidth

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

We demonstrate the first-ever silicon photonics enabled hyper-wideband RF spread-spectrum link. A silicon photonic mode-locked laser encoded with a four-channel silicon phase encoder is used to generate optical carriers that coherently demodulate a received RF signal spanning an instantaneous bandwidth greater than 85% of the center frequency (12GHz/14GHz). This allows ...

Cost-optimized submarine cables using massive spatial parallelism

  • Chraplyvy A.
  • Dar R.
  • Fevrier H.
  • Grubb S.
  • Huang K.
  • Winzer P.
  • Zsigmond S.

We study the techno-economics of submarine systems constrained by a fixed electrical power supply. We show significant cost savings for high-capacity submarine systems using massive space-division multiplexing (SDM), even without assuming any savings from SDM-specific subsystem integration. Systems with about 100 parallel optical paths are shown to provide minimum cost/bit, ...

Novel Lattice Reduction Algorithms: Precoder reduction and vector perturbation tradeoffs

  • Guenach M.

In this letter we present a novel iterative lattice reduction algorithm in precoded multiple input multiple output (MIMO) transmission. A unified framework is developed for this purpose, to reduce the precoder maximum row norm by iteratively minimizing the weighted sum of the precoder rownorms. We show that at each iteration ...

Multilevel Continuous Polarization Modulation with High Spectral Efficiency in the Depolarization Channels

  • Li R.
  • Liu F.
  • Wang B.
  • Wang X.

Facing the challenges of spectrum shortage and complex depolarization effects in wireless communication, a multilevel continuous polarization modulation (MCPoM) scheme is investigated to achieve high spectral efficiency and improve the symbol error rate performance in the practical depolarization channels. The principle of the MCPoM modulation is stated in details on ...