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Although beamforming optimization problems in full-duplex communication systems can be optimally solved with the semidefinite relaxation (SDR) approach, its computational complexity increases rapidly when the problem size increases. In order to circumvent this issue, in this paper, we propose an alternating direction of multiplier method (ADMM) which minimizes the augmented Lagrangian of the dual of the SDR and handles the inequality constraints with the use of slack variables. The proposed ADMM is then applied for optimizing the relay beamformer to maximize the secrecy rate.

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32 Views

Achieving high resolution time-of-arrival (TOA) estimation in multipath propagation scenarios from bandlimited observations of communication signals is challenging because the multipath channel impulse response (CIR) is not bandlimited. Modeling the CIR as a sparse sequence of Diracs, TOA estimation becomes a problem of parametric spectral inference from observed bandlimited signals. To increase resolution without arriving at unrealistic sampling rates, we consider multiband sampling approach, and propose a practical multibranch receiver for the acquisition.

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22 Views

Backscatter communication (BSC) is emerging as the core technology for pervasive sustainable internet-of-things applications. However, owing to the resource-limitations of passive tags, this work targets at maximizing the achievable sum-backscattered-throughput by jointly optimizing the transceiver (TRX) design at the full-duplex multiantenna reader and backscattering coefficients (BC) at the single antenna tags.

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12 Views

Energy efficient resource allocation in interference networks is a challenging global optimization problem. The main issue is that the computational complexity grows exponentially in the number of variables. In general, resource allocation in interference networks requires optimizing jointly over achievable rates and transmit powers. However, close scrutiny reveals that the non-convexity stems mostly from the powers while the problem is linear in the rates.

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19 Views

We re-examine the problem of designing low-complexity detectors and their performance analysis for the 3-node oneway decode-and-forward (DF) relay network, where the destination has the statistical channel state information (CSI) of the source-relay link, and the instantaneous CSI of both the source-destination and relay-destination links. Recently proposed detection schemes, such as the piece-wise linear detector (PLD), achieve near-optimal error performance with linear complexity (with respect to the modulation size).

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7 Views

Generalized frequency division multiplexing (GFDM) is considered a nonorthogonal waveform and can cause difficulties when used in the spatial multiplexing mode of a multiple-input-multiple-output (MIMO) scenario. In this paper, a class of GFDM prototype filters, in which the GFDM system is free from inter subcarrier interference, is investigated, enabling frequency-domain decoupling during processing at the GFDM receiver. An efficient MIMO-GFDM detection method based on depth-first sphere decoding is subsequently proposed with this class of filters.

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43 Views

Internet-of-Things (IoT) networks are envisioned to typically
include a massive number of devices with sporadic and low-latency
uplink service needs. This paper presents a blind
demixing approach to support the data recovery of multiple
simultaneous and unscheduled device transmissions without
a priori channel state information (CSI). The proposed joint
receiver leverages the group sparse bilinear characteristics
of the underlying problem that involves active device detection
and data recovery. We exploit the manifold geometry

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44 Views

Internet-of-Things (IoT) networks are envisioned to typically
include a massive number of devices with sporadic and low-latency
uplink service needs. This paper presents a blind
demixing approach to support the data recovery of multiple
simultaneous and unscheduled device transmissions without
a priori channel state information (CSI). The proposed joint
receiver leverages the group sparse bilinear characteristics
of the underlying problem that involves active device detection
and data recovery. We exploit the manifold geometry

Categories:
33 Views

We describe a general framework for designing and embedding a fingerprint at the physical layer of a wireless network to achieve authentication with enhanced security and stealth. Fingerprint embedding is a key-aided process of superimposing a low-power tag to the primary message waveform for the purpose of authenticating the transmission. The tag is uniquely created from the message and key, and successful authentication is achieved when the correct tag is detected by the receiver.

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42 Views

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