Low-cost Radio Frequency Research Articles

Advanced RF and microwave functions based on an integrated optical frequency comb source.

We demonstrate advanced transversal radio frequency (RF) and microwave functions based on a Kerr optical comb source generated by an integrated micro-ring resonator. We achieve extremely high performance for an optical true time delay aimed at tunable phased array antenna applications, as well as reconfigurable microwave photonic filters. Our results agree well with theory. We show that our true time delay would yield a phased array antenna with features that include high angular resolution and a wide range of beam steering angles, while the microwave photonic filters feature high Q factors, wideband tunability, and highly reconfigurable filtering shapes. These results show that our approach is a competitive solution to implementing reconfigurable, high performance and potentially low cost RF and microwave signal processing functions for applications including radar and communication systems.

The development and implementation of low cost radio frequency amplifier chip test solution based on PXI system

The development and implementation of low cost radio frequency amplifier chip test solution based on PXI system

Micro-Trivium: A lightweight algorithm designed for radio frequency identification systems

Distributed sensor networks have been widely applied to healthcare, environmental monitoring and management, intelligent transportation, and other fields in which network sensors collect and transmit information about their surrounding environment. Radio frequency identification technology transmits an object’s identification as a unique serial number—using radio waves as the transmission carrier—and is becoming an important building block for distributed sensor networks. However, the security of radio frequency identification systems is a major industrial concern that can significantly hinder the market growth of distributed sensor networks. Trivium is a well-known lightweight synchronous stream cipher that was submitted to the European eSTREAM project in April 2005. In this article, we generalize Trivium to the Trivium-Model algorithm and highlight that security is mainly determined by the internal state bits and the number of nonlinear terms. We propose principles for choosing parameters and generating better parameters that are feasible for low-cost radio frequency identification tags in distributed sensor networks. The new algorithm, named Micro-Trivium, requires less power and a smaller chip area than the original Trivium, which is proven using experimental data and results. Mathematical analysis shows that using Micro-Trivium is as secure as using Trivium.

Graphene-Flakes Printed Wideband Elliptical Dipole Antenna for Low-Cost Wireless Communications Applications

This letter presents the design, manufacturing and operational performance of a graphene-flakes based screenprinted wideband elliptical dipole antenna operating from 2 GHz up to 5 GHz for low cost wireless communications applications. To investigate radio frequency (RF) conductivity of the printed graphene, a coplanar waveguide (CPW) test structure was designed, fabricated and tested in the frequency range from 1 GHz to 20 GHz. Antenna and CPW were screen-printed on Kapton substrates using a graphene paste formulated with a graphene to binder ratio of 1:2. A combination of thermal treatment and subsequent compression rolling is utilized to further decrease the sheet resistance for printed graphene structures, ultimately reaching 4 Ohm/sq. at 10 {\mu}m thicknesses. For the graphene-flakes printed antenna an antenna efficiency of 60% is obtained. The measured maximum antenna gain is 2.3 dBi at 4.8 GHz. Thus the graphene-flakes printed antenna adds a total loss of only 3.1 dB to an RF link when compared to the same structure screen-printed for reference with a commercial silver ink. This shows that the electrical performance of screen-printed graphene flakes, which also does not degrade after repeated bending, is suitable for realizing low-cost wearable RF wireless communication devices.

Achieving protection against man-in-the-middle attack in HB family protocols implemented in RFID tags

Purpose In the past few years, HB-like protocols have gained much attention in the field of lightweight authentication protocols due to their efficient functioning and large potential applications in low-cost radio frequency identification tags, which are on the other side spreading so fast. However, most published HB protocols are vulnerable to man-in-the-middle attacks such as GRS or OOV attacks. The purpose of this research is to investigate security issues pertaining to HB-like protocols with an aim of improving their security and efficiency. Design/methodology/approach In this paper, a new and secure variant of HB family protocols named HB-MP* is proposed and designed, using the techniques of random rotation. The security of the proposed protocol is proven using formal proofs. Also, a prototype of the protocol is implemented to check its applicability, test the security in implementation and to compare its performance with the most related protocol. Findings The HB-MP* protocol is found secure against passive and active adversaries and is implementable within the tight resource constraints of today’s EPC-type RFID tags. Accordingly, the HB-MP* protocol provides higher security than previous HB-like protocols without sacrificing performance. Originality/value This paper proposes a new HB variant called HB-MP* that tries to be immune against the pre-mentioned attacks and at the same time keeping the simple structure. It will use only lightweight operations to randomize the rotation of the secret.

Versatile Sensing Platform Assemble on Flexible Organic Transistors

Organic thin-film transistors (OTFTs), as the essential parts of modern electronic devices, have found a wide range of application paradigms in low-cost radio frequency identification (RFID), large-area display and portable high-performed sensors. Being an important type of the OTFTs family, organic electrochemical transistors(OECTs) demonstrate high stability in aqueous electrolytes for long time, making it promising for the real-time chemical and biological sensing applications in electrolytes. Considering these desirable properties, OECTs have been extensively investigated as a feasible platform for a wide range of sensing scenarios, including ions, glucose, uric acid, dopamine, DNA, bacteria and cells, etc. Nevertheless, these thoroughly investigated OECTs sensors are solely fabricated on the conventional planar structures (silicon wafer, glass, and PET, etc), making it difficult to be integrated with the flexible and wearable electronic systems. To alleviate this problem, Olle Inganäs et al reported a novel approach for the construction of fiber-based OECTs assembled on the textile monofilaments with 10–100 μm diameters. The flexible woven electrochemical transistors demonstrate fast switching time and therefore represent a significant step towards the realization of electronic textiles. However, no functionalized fiber OECTs devices have ever been investigated for the high performance biological sensing applications. Up until now, it is still tricky to deal with the fabrication and functionalization of fiber-based OECTs device for sensing applications. To alleviate the challenge, we hereby report for the first time, the fabrication and functionalization of fiber-based OECTs as a versatile sensing platform for high-performed biological sensors. The fiber OECTs exhibit high electric conductivity, mechanical flexibility and extremely light weighted. Different form their conventional planar counterparts, these weavable fiber-based OECT devices demonstrate ultrahigh flexibility, making it a potential candidate for the realization of cutting-edge wearable electronics. The functionalized devices were successfully fabricated for various chemical and biological sensing scenarios, including pH, metal ions, glucose, dopamine and uric acid. igh performance fiber-based OECT glucose sensor was realized by the using of functionalized CHIT-graphene flakes/GOx/Pt fiber gate electrode. The low detection limit of the device to glucose was about 30nM. Similarly, flexible fiber OECT dopamine sensor and uric acid sensor could also been fabricated using the modified fiber gate Nafion (1.0%)–graphene/Pt and UOx/PANI/Nafion-graphene/Pt, respectively. The detection limit of these sensors was as low as several to a few tens nM, which was approximately 2-3 orders of magnitude lower than the conventional electrochemical approaches. Meanwhile, desirable selectivity property could be achieved through the proper modification of the gate electrode. The sensitivity and selectivity features of these fiber based OECT sensors could be simultaneously enhanced by the proper co-modification of bio-molecules, biocompatible polymers and nano-materials on the surface of gate electrode. More interestingly, the flexible fiber-based OECTs afford for the no-invasive detection of biological elements in human saliva. In summary, the successfully fabricated high-performance fiber-based OECT device holds great potential for a wide range of applications, including point-of-care tests, clinic diagnosis and therapy, fitness tracking and body-condition monitoring.

Formation of nanocrystalline GeSn thin film on Si substrate by sputtering and rapid thermal annealing

Nanocrystalline Ge1-xSnx thin films have been formed after rapid thermal annealing of sputtered GeSn layers. The alloy films were deposited onto the Silicon (100) substrate via low cost radio frequency magnetron sputtering. Then, the films were annealed by rapid thermal annealing at 350 °C, 400 °C, and 450 °C for 10 s. The morphological, structural, and optical properties of the layers were investigated with field emission scanning electron microscopy (FESEM), Energy-dispersive X-ray spectroscopy (EDX), Raman spectroscopy, and high-resolution X-ray diffraction (HR-XRD). The Raman analysis showed that the only observed phonon mode is attributed to Ge-Ge vibrations. Raman phonon intensities of GeSn thin films were enhanced with increasing the annealing temperature. The results clearly revealed that by increasing the annealing temperature the crystalline quality of the films were improved. The XRD measurements revealed the nanocrystalline phase formation in the annealed films with (111) preferred orientation. The results showed the potentiality of using the sputtering technique and rapid thermal anneal to produce crystalline GeSn layer.

Multifunctional radio-frequency generator for cold atom experiments

We present a low cost radio-frequency (RF) generator suitable for experiments with cold atoms. The RF source achieves a sub-hertz frequency with tunable resolution from 0 MHz to 400 MHz and a maximum output power of 33 dBm. Based on a direct digital synthesizer (DDS) chip, we implement a ramping capability for frequency, amplitude and phase. The system can also operate as an arbitrary waveform generator. By measuring the stability in a duration of 600 s, we find the presented device performs comparably as Agilent33522A in terms of short-term stability. Due to its excellent performance, the RF generator has been already applied to cold atom trapping experiments.

A Passive RF Sensor for Detecting Simultaneous Partial Discharge Signals Using Time–Frequency Analysis

In this paper, a passive radio-frequency (RF) sensor has been presented for non-invasive radiometric detection of simultaneous partial discharge (PD) signals in high-voltage (HV) equipment. The sensor is a multi-resonator-based passive circuit with an antenna for capturing PD signals. The low-cost RF sensors are installed in HV sensing units for monitoring multiple units simultaneously. Each sensor captures PD signal and processes it with distinct spectral signatures as identification data bits and transmits the signal to a single sampling channel. From the captured RF signal, both the PD level and the source identification can be retrieved. Our proposed passive sensor addresses both aspects of PD monitoring, PD detection, and faulty source identification. Moreover, in identifying the data bits, the time–frequency analysis is utilized for superior detectability. This analysis enables the detection of multiple PD events separated by a defined time delay, although they occur at the same instance. Thus, the sensor can distinguish simultaneous PD occurrences from multiple sources, which is a novel contribution in PD detection. The proposed sensor system provides low-cost, passive condition monitoring of HV units in a distribution substation.

A Low-Cost and Complexity Multibeam RF Transmit Beamformer for Wideband LFM Radar

This letter presents a simple and efficient multibeam radio-frequency (RF) beamformer for wideband linear frequency modulation waveform transmission. A time-varying weighting method instead of the true time delay technique is proposed. The process of beamforming weighting is implemented by quadrature modulators in the transmit (TX) path. As the RF operation frequency changes, the modulating phase-shift coefficients in baseband vary in time series. Since this beamformer is easy to perform at the element level, the simultaneous and independent TX multiple beamforming has become achievable. Moreover, the quality of the output signal and the process of wideband equalization among multiple channels are considered. The channel imbalances over a broad frequency range are compensated by time-varying predistortion coefficients. To validate the practical feasibility of this method, a prototype system with four-element antenna array is designed and tested. Single-beam and simultaneous two-beam patterns steering between ± 30° over 500 MHz at the center frequency 2.45 GHz have been demonstrated experimentally.

A Low-cost RFID/GPS Location Sensing Algorithm for Urban Infrastructure

Low-cost Radio Frequency Identification (RFID) location sensing algorithm is practical and crucial for urban infrastructure location. Current RFID location algorithms are based on fixed multiple RFID reader or reference points (reader or tag) with known position, which is cost and difficult to deployment in urban environment. The objective of this study is to develop a low-cost location sensing algorithm using RFID technique to locate urban infrastructure. This paper presents an algorithm based on multilateration with the integration of mobile RFID and Global Position System (GPS). The mobility of RFID reader can measure many distances between different RFID reader positions and target tag which represent multilateration. The GPS provides coordination of RFID reader. The location of tag is calculated based on triangle geometric property. The redundant observation is adopted to get the optimum location. In practice, the only one RFID reader is necessary, thus the cost is reduced hardly. The performance and accuracy assessment are conducted in field experiment. The experiment proves that the proposed low-cost location sensing algorithm is able to location the urban infrastructure with smaller position error. The lower cost makes it even more economically feasible than other algorithm.

Modulation-format-independent OSNR monitoring insensitive to cascaded filtering effects by low-cost coherent receptions and RF power measurements.

Optical signal-to-noise ratio (OSNR) monitoring is indispensable for ensuring robust and flexible optical networks that provide failure diagnosis, dynamic lightpath provisioning and modulation format adaptation. We propose and experimentally demonstrate a low-cost, modulation-format-independent OSNR monitoring scheme utilizing reduced-complexity coherent receptions, electrical filtering and radio frequency (RF) power measurements. By measuring the RF power of the coherently received baseband signals at three different frequency components, the proposed OSNR monitor is also insensitive to spectral narrowing induced by cascaded wavelength selective switches (WSSs). We experimentally demonstrate accurate data-format-transparent and filtering-effect-insensitive OSNR monitoring for 25-Gbaud dual-polarization (DP-) transmissions with QPSK, 16-QAM and 64-QAM signals over various distances with different amount of filtering effects by cascaded WSSs. We further characterize the influence of different system parameters, such as the bandwidth of the electrical low-pass filter, the laser frequency offset and laser linewidth on the accuracy of the proposed OSNR monitor. The robustness of the proposed OSNR monitoring scheme to fiber nonlinearities, calibration parameter mismatches and variations of WSS parameters are also investigated.

RFID Authentication with Un-Traceability and Forward Secrecy in the Partial-Distributed-Server Model

Secure authentication of low cost Radio Frequency Identification (RFID) tag with limited resources is a big challenge, especially when we simultaneously consider anonymity, un-traceability, and forward secrecy. The popularity of Internet of Things (IoT) further amplifies this challenge, as we should authenticate these mobile tags in the partialdistributed-server environments. In this paper, we propose an RFID authentication scheme in the partial-distributed-server environments. The proposed scheme owns excellent performance in terms of computational complexity and scalability as well as security properties. key words: authentication, RFID, anonymity, distributed servers, error correction code

RFID Anti-Counterfeiting for Retailing Systems

Counterfeiting is one of the most serious problems in the consumer market. One promising approach for anti-counterfeiting is to attach a low-cost Radio-frequency Identification (RFID) tag to the product authentication. In this paper, we propose an RFID system for detecting counterfeiting products. This RFID system consists of the tag authentication protocol and the database correction protocol. We use the tag authentication protocol for authenticating tags without revealing their sensitive information. This protocol also allows the customer to freely inquire the tag. To prevent the widespread of the counterfeit products, we use the tag status information along with tag identity information. Meanwhile, the database correction protocol guarantees the correctness of the tag status. Our anti-counterfeiting system is the first work considering the seller who plays an important role in the consumer product supply chain. Finally, we show that anti-counterfeiting system is quite secure against counterfeiting and the tag authentication protocol is lightweight enough to be implemented in RFID-based applications.

Wireless infrastructure protection using low-cost radio frequency fingerprinting receivers

Low-data-rate wireless networks incorporated in critical infrastructure applications can be protected through 128-bit encryption keys and address-based access control lists. However, these bit-level credentials are vulnerable to interception, extraction and spoofing using software tools available free of charge on the Internet. Recent research has demonstrated that wireless physical layer device fingerprinting can be used to defend against replay and spoofing attacks. However, radio frequency (RF) fingerprinting typically uses expensive signal collection systems; this is because fingerprinting wireless devices with low-cost receivers has been reported to have inconsistent accuracy. This paper demonstrates a robust radio frequency fingerprinting process that is consistently accurate with both high-end and low-cost receivers. Indeed, the results demonstrate that low-cost software-defined radios can be used to perform accurate radio frequency fingerprinting and to identify spoofing attacks in critical IEEE 802.15.4-based infrastructure networks such as ZigBee.

A Formally Verified Mutual Authentication Protocol for Low-Cost RFID Tags

In this paper, we propose a lightweight mutual authentication protocol for low-cost Radio Frequency IDentification (RFID) tags. Although RFID systems promise a fruitful future, security and privacy concerns have affected the proliferation of the RFID technology. The proposed protocol aims to protect RFID tags against a wide variety of attacks and especially Denial of Service (DoS) attacks. We found that the majority of the proposed protocols failed to resist this kind of attack. To analyse our proposed protocol, we provide an informal analysis. In addition, we formally analyse the security of the proposed protocol via using automated formal verification tools such as CasperFDR and AVISPA. We also employed an up-to-date privacy model to evaluate the privacy of the RFID protocol. The results show that the proposed protocol achieves tag’s data secrecy, privacy and authentication under the presence of a passive adversary.

Demonstration of radio-frequency response of amorphous IGZO thin film transistors on the glass substrate

The relatively high-mobility metal-oxide thin-film transistors (TFTs) have the potential to realize radio-frequency (RF) circuits operating in the megahertz regime. Here, we investigate the RF performance of amorphous indium gallium zinc oxide (a-IGZO) TFTs on the glass substrate with the sputtered channel layer. The device exhibits a high current density of 22.6mA/mm by employing thin bi-layer Al2O3/SiO2 gate dielectrics. The 1.5μm gate length device achieves a current gain cutoff frequency fT of 384MHz and a maximum frequency of oscillation fmax of 1.06GHz. The record high RF response among the amorphous oxide channels makes it possible to explore new large-area electronics applications, such as low-cost radio frequency identification (RFID) tags. Furthermore, the corresponding small signal parameters were extracted and the voltage dependences of RF response were studied.

Widely linear digital self-interference cancellation in direct-conversion full-duplex transceiver

This paper addresses the modeling and cancellation of self-interference in full-duplex direct-conversion radio transceivers, operating under practical imperfect radio frequency (RF) components. First, detailed self-interference signal modeling is carried out, taking into account the most important RF imperfections, namely, transmitter power amplifier nonlinear distortion as well as transmitter and receiver IQ mixer amplitude and phase imbalances. The analysis shows that after realistic antenna isolation and RF cancellation, the dominant self-interference waveform at the receiver digital baseband can be modeled through a widely linear transformation of the original transmit data, opposed to classical purely linear models. Such widely linear self-interference waveform is physically stemming from the transmitter and receiver IQ imaging and cannot be efficiently suppressed by classical linear digital cancellation. Motivated by this, novel widely linear digital self-interference cancellation processing is then proposed and formulated, combined with efficient parameter estimation methods. Extensive simulation results demonstrate that the proposed widely linear cancellation processing clearly outperforms the existing linear solutions, hence enabling the use of practical low-cost RF front ends utilizing IQ mixing in full-duplex transceivers.

EPCGen2 pseudorandom number generators: analysis of J3Gen.

This paper analyzes the cryptographic security of J3Gen, a promising pseudo random number generator for low-cost passive Radio Frequency Identification (RFID) tags. Although J3Gen has been shown to fulfill the randomness criteria set by the EPCglobal Gen2 standard and is intended for security applications, we describe here two cryptanalytic attacks that question its security claims: (i) a probabilistic attack based on solving linear equation systems; and (ii) a deterministic attack based on the decimation of the output sequence. Numerical results, supported by simulations, show that for the specific recommended values of the configurable parameters, a low number of intercepted output bits are enough to break J3Gen. We then make some recommendations that address these issues.

Combining Rabin cryptosystem and error correction codes to facilitate anonymous authentication with un-traceability for low-end devices

Secure authentication of low cost Radio Frequency Identification (RFID) with low computing capacity is a big challenge, due to the constraint of the limited resources and the privacy concern of their mobility and traceability. Here, we not only concern authentication but also privacy (anonymity and un-traceability) to protect privacy of these mobile devices and their holders. In this paper, we delicately combine Rabin cryptosystem and error correction codes to design lightweight authentication scheme with anonymity and un-traceability. Compared to its previous counterpart [4], the proposed schemes improve the number of supported tags from O(k) to O(2k), where k is the dimension of the codes. The scheme is attractive to low-end devices, especially those low-cost cryptographic RFIDs. We, additionally, show the security weaknesses of a recently published Rabin cryptosystem-based RFID authentication scheme.