FM-CW compact reflectometer using DDS signal generation

2021 ◽  
Vol 16 (11) ◽  
pp. C11005
Author(s):  
A. Silva ◽  
J. Dias ◽  
J. Santos ◽  
F. da Silva ◽  
B. Gonçalves
Keyword(s):  
Integrated Circuits ◽  
Communication Systems ◽  
Low Cost ◽  
Ultra Wideband ◽  
Signal Generation ◽  
Single Chip ◽  
Constant Frequency ◽  
Band Frequency ◽  
Full Band ◽  
External Clock

Abstract A prototype of a compact coherent fast frequency sweeping RF back-end is being developed at IPFN-IST using commercial Monolithic Microwave Integrated Circuits (MMIC). On this work we present the usability of this concept of compact reflectometry associated with a Direct Digital Synthesis (DDS) source. Flexibility is one of the design goals for the back-end prototype, so that it can easily match the required frequency range. The backend alone covers the NATO J-band (10 GHz to 20 GHz) and is designed to drive external full band frequency multipliers, resulting in an ultra-wideband coverage of up to 140 GHz. FM-CW radar precision is strongly dependent on the probing source linearity. DDS nowadays plays an important role in signal generation in many fields of applications for communication systems as well as in radar technology. Modern DDSs are fully integrated, low-cost, single chip solutions that only need an external clock source for generating sinusoidal output signals up to several gigahertz. The DDS benefits from the totally digital generation of the output signal, which allows full control of the signal’s frequency and phase, both with very high precision and resolution. Recent implementations feature automatic sweeping capability, thus allowing the DDS to generate very linear and agile frequency chirps, assuming a high quality and constant frequency reference clock source. We propose to implement a DDS signal generation solution with the capability of a full band sweep in 1 μs. On the receiver side the IF and reference signals will be digitised allowing the use of high flexible data processing techniques. Input/output signals will allow the synchronisation of several systems.

scholarly journals Wireless Body Sensor Communication Systems Based on UWB and IBC Technologies: State-of-the-Art and Open Challenges

Sensors ◽  
2020 ◽  
Vol 20 (12) ◽  
pp. 3587
Author(s):  
Ivana Čuljak ◽  
Željka Lučev Vasić ◽  
Hrvoje Mihaldinec ◽  
Hrvoje Džapo
Keyword(s):  
Communication Systems ◽  
Short Range ◽  
Ieee 802.15.4 ◽  
State Of The Art ◽  
Low Cost ◽  
Ultra Wideband ◽  
Body Area ◽  
The Subject ◽  
Wireless Interfaces ◽  
User Friendly

In recent years there has been an increasing need for miniature, low-cost, commercially accessible, and user-friendly sensor solutions for wireless body area networks (WBAN), which has led to the adoption of new physical communication interfaces providing distinctive advantages over traditional wireless technologies. Ultra-wideband (UWB) and intrabody communication (IBC) have been the subject of intensive research in recent years due to their promising characteristics as means for short-range, low-power, and low-data-rate wireless interfaces for interconnection of various sensors and devices placed on, inside, or in the close vicinity of the human body. The need for safe and standardized solutions has resulted in the development of two relevant standards, IEEE 802.15.4 (for UWB) and IEEE 802.15.6 (for UWB and IBC), respectively. This paper presents an in-depth overview of recent studies and advances in the field of application of UWB and IBC technologies for wireless body sensor communication systems.

Design and analysis of CPW-fed compact planar antennas for ultra wideband communication systems

2016 ◽  
Author(s):  
◽  
Haitham Alsaif
Keyword(s):  
Communication Systems ◽  
High Performance ◽  
Low Cost ◽  
Single Layer ◽  
Ultra Wideband ◽  
University Of Missouri ◽  
Uwb Antennas ◽  
Operating Frequency Range ◽  
Performance Results ◽  
Compact Planar

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT REQUEST OF AUTHOR.] In this research, three new designs of planar compact ultra-wideband (UWB) antennas have been studied, simulated, and experimentally measured. Their structures are not complicated in design, easy in fabrication with low cost. They are in different physical sizes and considered small compared to many recent published UWB antennas that have similar performance. The proposed antennas have ultra-wide bandwidth that cover the entire bandwidth allocated by FCC for such applications. They are made to be planar structure with a single layer in order to be easier in fabrication and for use in wireless devices and applications. The used feeding technique is coplanar wave-guide (CPW) in all of them due to the great advantages of this feeding methodology. Each design has certain more superiority over the others either in terms of operating frequency range, power gain, radiation pattern, or structure size. Although, all compact patch antennas demonstrate high performance results and are very suitable for ultra-wideband systems. Finally, since there are a variety of ultra-wideband applications with several characteristics requirements, the research is composed of three different sizes of compact planar single layers antennas. These antennas have similar or better performance than some other large size designs, which makes it suitable for very compact wireless gadgets. Thus, the ultra-wideband (UWB) systems designer will be able to select the most appropriate design for the application based on the antenna characterizes and size.

Design of V-band Full Band Frequency Tripler Based on Low-cost Schottky Diodes

2021 ◽  
Author(s):  
Peiwen Yu ◽  
Le Ren ◽  
Chunmin Wang ◽  
Jinping Xu
Keyword(s):  
Low Cost ◽  
Schottky Diodes ◽  
Band Frequency ◽  
V Band ◽  
Full Band

scholarly journals Ultra-Wideband MM Wave System and RF Modules

2021 ◽  
Author(s):  
Albert Sabban
Keyword(s):  
Communication Systems ◽  
Dynamic Range ◽  
Noise Figure ◽  
Signal To Noise Ratio ◽  
Low Cost ◽  
Direction Finding ◽  
High Gain ◽  
Ultra Wideband ◽  
Wave System ◽  
Wave Direction

Compact wideband RF modules are crucial in mm-wave direction finding systems, radars, seekers, and communication systems. This chapter discusses new integrated wideband mm-wave RF modules. It also discusses the design and development of a compact wideband (18–40 GHz) frontend and a wideband (18–40 GHz) switch bank filter (SBF). The frontend electrical specifications determine the system signal-to-noise ratio and the system dynamic range. This chapter presents a low-cost integrated 18–40 GHz wideband compact frontend with a 47 dBm high power limiter. The frontend consists of two channels: a high gain and low gain channel. Wideband MMIC switches are employed to select the required channel. The gain of the high gain channel is around 27 dB with ±1 dB flatness. The noise figure of the module is around 9 dB. This chapter also presents a low-cost, integrated, 18–40 GHz wideband compact SFB module. The wideband SFB consists of three wideband side-coupled microstrip filters. The SFB MIMIC switches operate in the 18 to 40 GHz frequency range and are used to select the required filter. The insertion loss of each filter section is less than 11.5 dB ±1.5 dB. The novelty of this research is the development of compact, integrated wideband mm-wave RF modules for direction finding and communication systems.

scholarly journals 28 GHz Single-Chip Transmit RF Front-End MMIC for Multichannel 5G Wireless Communications

Symmetry ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 1167
Author(s):  
Evgeny Erofeev ◽  
Vadim Arykov ◽  
Michael Stepanenko ◽  
Aleksei Voevodin ◽  
Aleksei Kogai ◽  
...  
Keyword(s):  
Wireless Networks ◽  
Integrated Circuits ◽  
Millimeter Wave ◽  
Communication Systems ◽  
Phase Shifter ◽  
Single Chip ◽  
Power Added Efficiency ◽  
Front End ◽  
Rf Front End ◽  
Digital Phase Shifter

Millimeter-wave wireless networks of the new fifth generation (5G) have become a primary focus in the development of the information and telecommunication industries. It is expected that 5G wireless networks will increase the data rates and reduce network latencies by an order of magnitude, which will create new telecommunication services for all sectors of the economy. New electronic components such as 28 GHz (27.5 to 28.35 GHz) single-chip transmit radio frequency (RF) front-end monolithic microwave integrated circuits (MMICs) will be required for the performance and power consumption of millimeter-wave (mm-wave) 5G communication systems. This component includes a 6-bit digital phase shifter, a driver amplifier and a power amplifier. The output power P3dB and power-added efficiency (PAE) are 29 dBm and 19.2% at 28 GHz. The phase shifter root-mean-square (RMS) phase and gain errors are 3° and 0.6 dB at 28 GHz. The chip dimensions are 4.35 × 4.40 mm.

scholarly journals Physical-Layer Security Improvement with Reconfigurable Intelligent Surfaces for 6G Wireless Communication Systems

Sensors ◽  
2021 ◽  
Vol 21 (4) ◽  
pp. 1439
Author(s):  
Janghyuk Youn ◽  
Woong Son ◽  
Bang Chul Jung
Keyword(s):  
Wireless Communication ◽  
Physical Layer Security ◽  
Communication Systems ◽  
Low Cost ◽  
Physical Layer ◽  
Base Station ◽  
Wireless Communication Systems ◽  
Secrecy Rate ◽  
Pilot Signal ◽  
Time Division

Recently, reconfigurable intelligent surfaces (RISs) have received much interest from both academia and industry due to their flexibility and cost-effectiveness in adjusting the phase and amplitude of wireless signals with low-cost passive reflecting elements. In particular, many RIS-aided techniques have been proposed to improve both data rate and energy efficiency for 6G wireless communication systems. In this paper, we propose a novel RIS-based channel randomization (RCR) technique for improving physical-layer security (PLS) for a time-division duplex (TDD) downlink cellular wire-tap network which consists of a single base station (BS) with multiple antennas, multiple legitimate pieces of user equipment (UE), multiple eavesdroppers (EVEs), and multiple RISs. We assume that only a line-of-sight (LOS) channel exists among the BS, the RISs, and the UE due to propagation characteristics of tera-hertz (THz) spectrum bands that may be used in 6G wireless communication systems. In the proposed technique, each RIS first pseudo-randomly generates multiple reflection matrices and utilizes them for both pilot signal duration (PSD) in uplink and data transmission duration (DTD) in downlink. Then, the BS estimates wireless channels of UE with reflection matrices of all RISs and selects the UE that has the best secrecy rate for each reflection matrix generated. It is shown herein that the proposed technique outperforms the conventional techniques in terms of achievable secrecy rates.

scholarly journals A Local Oscillator Phase Compensation Technique for Ultra-Wideband Stepped-Frequency Continuous Wave Radar Based on a Low-Cost Software-Defined Radio

Sensors ◽  
2021 ◽  
Vol 21 (3) ◽  
pp. 780
Author(s):  
Kazunori Takahashi ◽  
Takashi Miwa
Keyword(s):  
Software Defined Radio ◽  
Initial Phase ◽  
Continuous Wave ◽  
Low Cost ◽  
Local Oscillator ◽  
The Other ◽  
Ultra Wideband ◽  
Single Frequency ◽  
Wave Radar ◽  
Stepped Frequency

The paper discusses a way to configure a stepped-frequency continuous wave (SFCW) radar using a low-cost software-defined radio (SDR). The most of high-end SDRs offer multiple transmitter (TX) and receiver (RX) channels, one of which can be used as the reference channel for compensating the initial phases of TX and RX local oscillator (LO) signals. It is same as how commercial vector network analyzers (VNAs) compensate for the LO initial phase. These SDRs can thus acquire phase-coherent in-phase and quadrature (I/Q) data without additional components and an SFCW radar can be easily configured. On the other hand, low-cost SDRs typically have only one transmitter and receiver. Therefore, the LO initial phase has to be compensated and the phases of the received I/Q signals have to be retrieved, preferably without employing an additional receiver and components to retain the system low-cost and simple. The present paper illustrates that the difference between the phases of TX and RX LO signals varies when the LO frequency is changed because of the timing of the commencement of the mixing. The paper then proposes a technique to compensate for the LO initial phases using the internal RF loopback of the transceiver chip and to reconstruct a pulse, which requires two streaming: one for the device under test (DUT) channel and the other for the internal RF loopback channel. The effect of the LO initial phase and the proposed method for the compensation are demonstrated by experiments at a single frequency and sweeping frequency, respectively. The results show that the proposed method can compensate for the LO initial phases and ultra-wideband (UWB) pulses can be reconstructed correctly from the data sampled by a low-cost SDR.

Angle and polarization-independent miniaturized UWB FSS design

2021 ◽  
pp. 1-9
Author(s):  
Yanning Yuan ◽  
Yuchen Zhao ◽  
Xiaoli Xi
Keyword(s):  
Design Method ◽  
Incident Angle ◽  
Stop Band ◽  
Single Layer ◽  
Wireless Systems ◽  
Frequency Selective Surface ◽  
Ultra Wideband ◽  
Band Frequency ◽  
Gain Enhancement ◽  
Polarization Independent

Abstract A single-layer ultra-wideband (UWB) stop-band frequency selective surface (FSS) has several advantages in wireless systems, including a simple design, low debugging complexity, and an appropriate thickness. This study proposes a miniaturized UWB stop-band FSS design. The proposed FSS structure consists of a square-loop and metalized vias that are arranged on a single layer substrate; it has an excellent angle and polarization-independent characteristics. At an incident angle of 60°, the polarization response frequencies of the transverse electric and magnetic modes only shifted by 0.003 f0 and 0.007 f0, respectively. The equivalent circuit models of the square-loop and metallized vias structure are analysed and the accuracy of the calculation is evaluated by comparing the electromagnetic simulation. The 20 × 20 array constitutes an FSS reflector with a unit size of 4.2 mm × 4.2 mm (less than one-twentieth of the wavelength of 3 GHz), which realizes an UWB quasi-constant gain enhancement (in-band flatness is <0.5 dB). Finally, the simulation results were verified through sample processing and measurement; consistent results were obtained. The FSS miniaturization design method proposed in this study could be applied to the design of passband FSS (complementary structure), antennas and filters, among other applications.

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