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Visible light communications (VLC) technology has recently emerged as a complementary technology to the indoor radio frequency (RF) networks. While the backhauling of the indoor RF networks has been supported by fiber optics, the backhauling of the VLC network is still an open research problem. Power line communications (PLC) has been considered as a possible solution for the VLC networks due to its...
The Internet of Things (IoT) has emerged as one of the focal points in the evolution of cellular networks, and has motivated the introduction of several features that facilitate Machine-Type Communications (MTC) in LTE networks. These features serve the MTC goals of reduced User Equipment (UE) modem cost and complexity, Coverage Enhancement (CE) to support UEs in remote radio locations, and an improved...
The multi-copy routing paradigm in Delay Tolerant Networks (DTNs) implies that increasing contact bandwidth leads to a decrease in data delivery delay and an improvement in throughput. With Hybrid Radio Frequency/Free Space Optical (RF/FSO) PHY layers, the high data rate FSO links can be used to increase the contact bandwidth. However, due to the highly directional nature of FSO links, broadcasting...
Measuring distance in short-range radio devices greatly enhances the user experience. The distance information gives the user the opportunity to make intelligent decisions to which device in range he may want to connect. Previous efforts using radio signal strength or ultra-wideband technologies have not shown to be successful. In this paper, a narrowband RF technique is presented that is based on...
System integration takes benefit from 3D stacking technology in a wide range of applications such as smart imagers, photonic, wide I/O memories and high-performance computing. The 700 mm2 ITAC 3D integration test platform contains a set of “Integrated Technological and Application Circuits” for process development, electrical and RF characterization, reliability, die stacking, warpage and underfilling...
A new direct conversion architecture design of a multi-standard transmitter supporting cellular standards (GSM, UMTS and Wimax), wireless personal and local area network standards (Bluetooth, Zigbee and IEE802.11 b/g) as well as Radio navigation standards (GPS, Galileo) is presented in this paper dedicated for rescue applications. Behind this high number of standards, the proposed optimization design...
This paper overviews the Defense Advanced Research Projects Agency (DARPA) Adaptive RF Technologies (ART) and Arrays at Commercial Timescales (ACT) programs. These programs seek to create adaptable and reusable RF hardware in order to lower nonrecurring engineering development costs and timelines for RF systems and to allow RF hardware to be adapted to new missions after fielding. To achieve this...
The proliferation of the wireless market has driven the demand for RF systems to dramatically increase functionality, frequency coverage, bandwidth, and efficiency; while simultaneously reducing power consumption and die size to save power and cost. For example, the highly complex RF systems in handset technology have seen a dramatic increase in frequency, operating bands, and complexity of signals...
Universal Software Radio Peripheral (USRP) and GNU Radio are well known Software Defined Radio (SDR) tools. The USRPs designed by Ettus Research are used without a deep knowledge of their performances. In this paper, we report our output power measurements using a USRP B210 driven by a GNU Radio program. Our results show that the obtained output power decreases as the selected central frequency increases...
Long Term Evolution (LTE) Networks are being planned to be upgraded to LTE Advanced along with increasing availability of Release 10 User Equipment (UEs) and Spectrum Availability for Carrier Aggregation. LTE Advanced brings a major step increase in Down Link and Uplink Throughputs and related spectral efficiencies. This paper explains the evolution of Frequency Division Duplex (FDD) throughputs for...
Long Term Evolution Advanced (LTE-A) supports a wide range of applications that continuously demand for more resources in order to satisfy the customers' needs. Starting from release 10, Carrier Aggregation (CA) technology has been embedded in the standard to increase the available resources and thus higher performance is offered to users. The Bidirectional real-time applications where large requirements...
With the rapid development of modern wireless communication systems, the visible light communication system using LED becomes popular due to the higher transmission speed and more reliable QoS. In this paper, we analyze the principle of VLC communication systems and make a field trial simulation using the single chip machine. The analysis of VLC indicates that the VLC communication system could help...
This paper describes a 56-Gb/s transimpedance amplifier with a level-shift circuit and double-feedback-loop (DFB) compensation architecture to achieve high input sensitivity. The level-shift circuit placed between a main transimpedance amplifier and a post amplifier mitigates the trade-off between the bandwidth and noise of the receiver, which reduces the input referred noise by 70%. The DFB compensates...
The LTE-Advanced and its related market factors present many challenges for the RF power amplifier (PA) and front end designs. This paper reviews some of the emerging techniques such as dynamic supply voltage modulation, reconfigurable PA, FET stacking and power combining to solve these challenges for silicon based PAs. These techniques with advanced CMOS and SiGe technologies can benefit the future...
As the mobile communication systems develop from 2G to 3G, people require a uniform-spectrum, uniform-architecture. Software radio provides a key solution to the interconnection of various communication architectures and radio standards with different spectrum, poor cooperation capability and so on. Sample rate conversion based software radio is a key technology to implement the interconnection. According...
Phased array receive/transmit systems are widely used in radar and electronic warfare applications. A low noise receive module for a phased array system operating at 3–6GHz band is designed, produced and validated. The measurement results are compared to the numerical results obtained from AWR Design Environment simulations.
The DARPA Arrays at Commercial Timescales (ACT) program seeks to lower the nonrecurring engineering costs and timeframe of designing and upgrading phased arrays through the use of a common hardware module that can be reused across many phased array missions and array sizes. The ACT program seeks to utilize elemental level digital beamforming to remove many of the fixed choices, e.g. array size, number...
A description and flight test results of the "First Flight" of Raytheon's prototype next-generation, Pod based, airborne Electronic Warfare (EW) system is presented. The system is powered by the airstream flowing through a submerged turbine connected to a generator. The primary recipient of this prime power is a wideband, polarization diverse, Active Electronically Scanned Array (AESA) with...
The rapidly changing RF landscape creates a requirement for flexible frequency access as well as the ability to move signals over long distances. This paper presents the characterization and experiments of a wide band photonics enabled transceiver. The architecture, SFDR, noise figure, and gain are presented, followed by the results of communications experiments involving up to 25 km of remoting fiber...
RF spectrum analysis hardware with instantaneous bandwidth of 40 GHz, resolution bandwidths down to 20 kHz, high sensitivity, and high dynamic range is presented. RF energy modulated on laser light (like RF-over-fiber links) is processed in a light-absorbing crystal. Up to 400,000,000 pixels per second are currently recorded, displayed, and analyzed.
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