The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Adjacent channel interference caused by intermodulation distortion adversely affects the network operations in next generation heterogeneous and dynamic spectrum access networks. Multitudes of radio access technologies make the receivers susceptible to harmful interference due to nonlinear RF front ends. In this paper we analyze the intermodulation distortion arising from pairwise interactions of...
In this paper, a new spectrum sharing model referred to as riding on the primary (RoP) is proposed for wireless- powered IoT devices with ambient backscatter communication capabilities. The key idea of RoP is that the secondary transmitter harvests energy from the primary signal, then modulates its information bits to the primary signal, and reflects the modulated signal to the secondary receiver...
In this work, we consider the problem of data decoding in media-based modulation systems. The underlying problem is sparse because only a subset of the available transmit antennas is activated in each symbol; additionally, only one of the different mirror patterns is activated depending on the unknown data bits. Thus, the data recovery problem involves recovery of a block-sparse vector, with the additional...
Hybrid beamforming (BF) is a widely considered strategy to enable downlink multiuser transmission for mmWave communication systems. However, current mmWave WiFi standard, the IEEE 802.11 ad, does not support hybrid BF because it could only serve one user at a time. Thus, it is important to implement hybrid BF based on IEEE 802.11.ad such that it could be applied in future mmWave WiFi. In this paper,...
In millimeter wave (mmWave) communication, analog and hybrid beamforming systems are proposed to reduce the number of RF chains when a large antenna array is utilized to achieve a high beamforming gain. In this paper, a new transmission scheme is first proposed by leveraging the hardware architecture of analog and hybrid beamforming to improve the spectral efficiency. The new scheme is called spatial...
Channel estimation allows millimeter wave (mmWave) MIMO communication systems to design pre-coders and combiners under different objective functions. Hybrid MIMO architectures provide a good trade-off power consumption-performance at mmWave frequencies, but most of the prior work on channel estimation for these structures assumes a narrowband channel model. In this paper, we propose a sparse approach...
In a practical large scale antenna system (LSAS) over the millimeter Wave (mmWave) bands, the implementation of hybrid beamforming structure plays an important role as it provides high precoding gains to overcome the high path loss and achieve sufficient link margins. While employing such large antenna arrays, it becomes challenging to estimate the mmWave channel using the conventional algorithms...
In this paper, we investigate joint beamforming for energy-throughput tradeoff in a sustainable cloud radio access network system, where multiple base stations (BSs) powered by independent renewable energy sources will collaboratively transmit wireless information and energy to the data receiver and the energy receiver simultaneously. In order to obtain the optimal joint beamforming design over a...
5G backhaul requires high bandwidth and hybrid Radio Frequency/ Free Space Optical (RF/FSO) Communication offers Gbps links. The weather affects availability of both mmW RF and FSO links. Below cloud ceiling, the availability of hybrid RF/FSO link is above 85.7% and it can only be used for deadline-constrained large data transfers. At 17–22km above ground, the bit error rate of FSO links reaches below...
Millimeter wave compact RF transmitter and receiver for 5G communication system are designed in this paper, which could be typically applied in massive MIMO system of 16 channels. The transmitter and receiver are designed using multilayered structure and highly-integrated chips to decrease the module size. The antenna feeding transition structure are designed using electromagnetic field simulation...
Energy harvesting has become very attractive due to the extended usage time of devices. Among several forms of recycling energy, radiofrequency (RF) harvesting has been suggested due to its wide availability mainly in urban areas. Its applications range from sensor nodes to charging low power consumption portable devices and depend on the amount of antennas. In this paper, we evaluate the feasible...
Cooperative energy relaying helps in improving the radio frequency (RF) energy transfer (ET) efficiency by harvesting the otherwise dissipated energy and then transferring it to the nearby energy receiver. The achievable RF-ET gains are strongly influenced by the relative relay placement (RP), which may cause blocking of the direct energy transfer (DET) path between RF source and receiver, or energy...
Coherent detection requires exact knowledge of the channel state information, which is often a challenging task in demanding practical applications. Based on this, non-coherent detection of differentially modulated signals can be considered as an alternative method. The present paper investigates the effects of in-phase/quadrature-phase imbalance (IQI), which are known to degrade the performance of...
An interference monitoring station is presented which detects, characterises and logs interference events. The system operates autonomously and continuously over multiple global navigation satellite system (GNSS) bands. With a bandwidth of up to 80 MHz, input resolution of 8 bit an overall data rate of approximately 1.3 Gbit/s can be supported. The interference detection is carried out in real-time,...
This paper presents a 900 M low-power, low-noise receiver frontend implemented using TSMC 0.18-μm CMOS technology. The inductorless frontend comprises a low-noise amplifier (LNA) using bulk injection, a mixer, and an active balun operating in the subthreshold region. The front end achieves a conversion gain of 33.7 dB, and a 2.9 dB single sideband noise figure. The chip consumes 5.9 mA from a 0.9-V...
In this paper, a novel adaptive leakage suppression method (LSM) for ultra-high frequency radio frequency identification reader is proposed. The leaking power is reflected instead of absorbed to avoid saturating baseband circuits. The principle and application of this LSM based on selected power reflection actively controlled by digital baseband are discussed. The RF front-end is fabricated in a 0...
We present a real-time TDOA localization testbed utilizing software defined radio and GPS based synchronization. A distributed software stack enables the localization of unknown signals by transporting the recorded baseband samples of several sensors over a backhaul network for centralized signal processing in a fusion center. To overcome the relatively large drifts of synchronization signals provided...
In an increasingly dense and complex environment identification of the radars by Radar Warning Receivers (RWR) has utmost importance. In this study the process of obtaining the meaningful pulse sequences from radars with jitter and agile Pulse Repetition Interval (PRI) types is investigated. The effectiveness of the deinterleaving algorithm can be measured by one of the critical elements, which is...
This paper proposes an instantaneous frequency measurement (IFM) receiver structure for electronic support measure (ESM) systems. The performance of instantaneous frequency (IF) measurement improves as the IFM receiver delay increases. However, it is observed that the increasing delay introduces ambiguity to the IF measurement In order to resolve the ambiguity, an algorithm which uses the IFM receiver...
Detection and localization of vessels can be carried out by exploiting the radiolocation approach. Nevertheless, the employment of radiolocalization far from the shore can be limited by the lack of enough receivers to perform a correct multi-lateration of the RF source. In order to solve this gap, mobile assets or base stations from different networks need to be exploited. In particular, within a...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.