394 research outputs found
Achieving Large Multiplexing Gain in Distributed Antenna Systems via Cooperation with pCell Technology
In this paper we present pCellTM technology, the first commercial-grade
wireless system that employs cooperation between distributed transceiver
stations to create concurrent data links to multiple users in the same
spectrum. First we analyze the per-user signal-to-interference-plus-noise ratio
(SINR) employing a geometrical spatial channel model to define volumes in space
of coherent signal around user antennas (or personal cells, i.e., pCells). Then
we describe the system architecture consisting of a general-purpose-processor
(GPP) based software-defined radio (SDR) wireless platform implementing a
real-time LTE protocol stack to communicate with off-the-shelf LTE devices.
Finally we present experimental results demonstrating up to 16 concurrent
spatial channels for an aggregate average spectral efficiency of 59.3 bps/Hz in
the downlink and 27.5 bps/Hz in the uplink, providing data rates of 200 Mbps
downlink and 25 Mbps uplink in 5 MHz of TDD spectrum.Comment: IEEE Asilomar Conference on Signals, Systems, and Computers, Nov.
8-11th 2015, Pacific Grove, CA, US
A Novel Denial of Service Vulnerability in Long Term Evolution Cellular Networks
Currently many cellular networks operate using the Long Term Evolution (LTE) protocol. Therefore, most mobile subscribers interact with LTE on a daily basis, and thus are affected by the security standards and mechanisms it implements. Here, we propose a vulnerability within the LTE protocol: the mobility management control signaling, which dictates how a user equipment (UE) synchronizes with an enhanced Node-B (eNodeB) to prevent intersymbol interference. Presented are the implications and the overall effects on the bit error rate (BER) of falsified signaling which forces a UE to incorrectly advance or delay its uplink timing. Specifically, we derive a lower bound on the BER for UE that is subjected to the aforementioned signaling. Our simulation results show that a non-zero BER can be guaranteed regardless of noise conditions. Finally, we propose encryption of this signaling to prevent such an attack
Simulating Cellular Communications in Vehicular Networks: Making SimuLTE Interoperable with Veins
The evolution of cellular technologies toward 5G progressively enables
efficient and ubiquitous communications in an increasing number of fields.
Among these, vehicular networks are being considered as one of the most
promising and challenging applications, requiring support for communications in
high-speed mobility and delay-constrained information exchange in proximity. In
this context, simulation frameworks under the OMNeT++ umbrella are already
available: SimuLTE and Veins for cellular and vehicular systems, respectively.
In this paper, we describe the modifications that make SimuLTE interoperable
with Veins and INET, which leverage the OMNeT++ paradigm, and allow us to
achieve our goal without any modification to either of the latter two. We
discuss the limitations of the previous solution, namely VeinsLTE, which
integrates all three in a single framework, thus preventing independent
evolution and upgrades of each building block.Comment: Published in: A. Foerster, A. Udugama, A. Koensgen, A. Virdis, M.
Kirsche (Eds.), Proc. of the 4th OMNeT++ Community Summit, University of
Bremen - Germany - September 7-8, 201
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