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- Keyword
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- Measurement (3)
- Ratiometric (3)
- Video streaming (3)
- WLAN (3)
- Wavelength (3)
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- 802.11e (2)
- Control (2)
- Electro-optics (2)
- Liquid Crystal (2)
- Liquid Crystals (2)
- Multimedia (2)
- PID (2)
- Performance evaluation (2)
- Quality of service (2)
- RARE (2)
- Routing protocols (2)
- WMNs (2)
- 1.409 GHz annular-ring loading ground plane impedance bandwidth microstrip patch antenna patch radiator slot antenna (1)
- 1.44 to 14.7 GHz genetic algorithm printed monopole antennas quadratic curves search space spline-based geometry (1)
- 1.575 GHz 1.710 to 1.880 GHz 1.920 to 2.170 GHz 10 dB annular-ring patch antenna cellular applications circular patch antenna miniature wideband patch antenna multimode devices portable wireless application (1)
- 1060XP fiber fiber edge filter macrobending loss (1)
- 2.97 to 12.77 GHz 5.15 to 5.825 GHz 9.8 GHz H-shaped slot high data rate wireless communication systems printed band-rejection UWB antenna tunable notch-frequency band (1)
- 3.1 to 15 GHz broad impedance bandwidth low-profile rolled planar antenna omnidirectional features planar monopole type antenna radiation efficiency radiation patterns (1)
- 3D geometry (1)
- Accuracy (1)
- Active probing (1)
- Adaptive video streaming (1)
- Affine (1)
- Algorithm (1)
- Algorithmic composition (1)
- Publication
Articles 1 - 30 of 64
Full-Text Articles in Engineering
Practical Sensor For Measurement Of Nitrogen, Dusan Popovic, Vladimir Milosavljevic, Steven Daniels
Practical Sensor For Measurement Of Nitrogen, Dusan Popovic, Vladimir Milosavljevic, Steven Daniels
Articles
This paper presents a method for precise measurement of atomic and molecular nitrogen in an oxygen-nitrogen dc plasma. This is achieved by monitoring the intensities of the atomic nitrogen spectral line at 821.6 nm and the molecular nitrogen bandhead at 337.1 nm, relative to the atomic oxygen spectral line at 844.7 nm. Oxygen is one of the most frequently used gases for surface chemical treatment, including deposition and etching, therefore the ability to measure and control the process and chemical composition of the process is essential. To validate this oxygen actimometry method for N2-xO2 (where x varies from 0 to …
Wireless Positioning Techniques: A Developer's Update, Seamus Rooney, Keith Gardiner, James Carswell
Wireless Positioning Techniques: A Developer's Update, Seamus Rooney, Keith Gardiner, James Carswell
Conference papers
This paper describes the current efforts to develop an open source, privacy sensitive, location determination software component for mobile devices. Currently in mobile computing, the ability of a mobile device to determine its own location is becoming increasingly desirable as the usefulness of such a feature enhances many commercial applications. There have been numerous attempts to achieve this from both the network positioning perspective and also from the wireless beacon angle not to mention the integration of GPS into mobile devices. There are two important aspects to consider when using such a system which are privacy and cost. This paper …
Experimental Measurement Of Overhead Associated With Active Probing Of Wireless Mesh Networks, Brian Keegan, Karol Kowalik
Experimental Measurement Of Overhead Associated With Active Probing Of Wireless Mesh Networks, Brian Keegan, Karol Kowalik
Conference papers
Wireless Mesh Networks (WMNs) represent the next generation wireless networks. The increased capacity of WMNs means that they are now capable of providing backhaul services traditionally maintained by wired networks. The attraction of WMNs is their ease of deployment and ability to self organise, self configure, and self heal. In order to successfully achieve this objective careful consideration must be applied when constructing a WMN. In order to optimise the operation of the network, data should traverse the network by means of the most efficient route. Characterisation and path selection will be determined by the routing algorithm coupled with the …
An Experimental Investigation Of Real-Time Video Transmission Over Ieee 802.11e Wlan Networks Using Txop, Nicola Cranley, Mark Davis
An Experimental Investigation Of Real-Time Video Transmission Over Ieee 802.11e Wlan Networks Using Txop, Nicola Cranley, Mark Davis
Conference papers
Real-time multimedia streaming applications require a strict bounded end-to-end delay and are considered to be bursty as each video frame is typically transmitted as a burst of packets. In this paper we show how the distribution of video frame sizes can be used to efficiently dimension the IEEE 802.11e TXOP limit parameter to efficiently deal with this burstiness in order to enhance the transmission of real-time video streaming services. Through experimental investigation, we show that by using the mean video frame size to dimension the TXOP limit parameter, the transmission delay for the video frame is reduced by 67% under …
Music Structure Segmentation Using The Azimugram In Conjunction With Principal Component Analysis, Dan Barry, Mikel Gainza, Eugene Coyle
Music Structure Segmentation Using The Azimugram In Conjunction With Principal Component Analysis, Dan Barry, Mikel Gainza, Eugene Coyle
Conference papers
A novel method to segment stereo music recordings into formal musical structures such as verses and choruses is presented. The method performs dimensional reduction on a time-azimuth representation of audio which results in a set of time activation sequences, each of which corresponds to a repeating structural segment. This is based on the assumption that each segment type such as verse or chorus has a unique energy distribution across the stereo field. It can be shown that these unique energy distributions along with their time activation sequences are the latent principal components of the time-azimuth representation. It can be shown …
The Effects Of Contention Among Stations On Video Streaming Applications Over Wireless Local Area Networks: An Experimental Approach, Nicola Cranley, Tanmoy Debnath
The Effects Of Contention Among Stations On Video Streaming Applications Over Wireless Local Area Networks: An Experimental Approach, Nicola Cranley, Tanmoy Debnath
Conference papers
Multimedia streaming applications have a large impact on the resource requirements of the WLAN. There are many variables involved in video streaming, such as the video content being streamed, how the video is encoded and how it is sent. This makes the role of radio resource management and the provision of QoS guarantees extremely difficult. For video streaming applications, packet loss and packets dropped due to excessive delay are the primary factors that affect the received video quality. In this paper, we experimentally analyse the effects of contention on the performance of video streaming applications with a given delay constraint …
The Capability Of The Edca Mechanism To Support Voice Traffic In A Mixed Voice/Data Transmission Over 802.11e Wlans: An Experimental Investigation, Miroslaw Narbutt, Mark Davis
The Capability Of The Edca Mechanism To Support Voice Traffic In A Mixed Voice/Data Transmission Over 802.11e Wlans: An Experimental Investigation, Miroslaw Narbutt, Mark Davis
Conference papers
In this paper we experimentally evaluate the capability of the EDCA mechanism to support voice traffic in a mixed voice/data transmission over 802.11e WLANs. In particular we investigate how real-time voice transmission can be supported by tuning four EDCA parameters, namely AIFSN, CWmin, CWmax and TXOP and how this impacts on background data transmission. The experimental set-up involves fifteen VoIP terminals sending bi-directional traffic between wired and wireless subnets and another station injecting various types of heavy background load to the wireless subnet. End-to-end voice transmission quality is predicted from time-varying transmission impairments with the use of the latest Appendix …
Analysis Of A Variable Speed Double-Fed Induction Generator Wind Turbine During Network Voltage Unbalance Conditions., Joseph Kearney, Michael Conlon
Analysis Of A Variable Speed Double-Fed Induction Generator Wind Turbine During Network Voltage Unbalance Conditions., Joseph Kearney, Michael Conlon
Conference papers
The behaviour of Double-Fed Induction Generators to supply network voltage unbalance is investigated. The paper shows the effects that voltage unbalance can have on a DFIG, using Matlab/Simulink. The results from simulations show that voltage unbalance affects both the induction generator and the rotor converter, due to the high unbalanced currents generated. The ability to modify the control strategy of a DFIG to compensate for voltage unbalance is outlined and simulations show the improvements to the performance of the DFIG.
Wideband Printed Monopole Design Using A Genetic Algorithm, Matthias John, Max Ammann
Wideband Printed Monopole Design Using A Genetic Algorithm, Matthias John, Max Ammann
Articles
A method for the design and optimisation of wide-band printed planar monopoles using a genetic algorithm is presented. This novel technique employs overlapping sub-patches which ensures electrical contact in such constellations where two sub-patches are touching only at the corner, hence re-ducing losses. The method was usd optimisation of wide-band printed planar monopoles using a genetic algorithm is presented. This novel technique employs overlapping sub-patches which ensures electrical contact in such constellations where two sub-patches are touching only at the corner, hence re-ducing losses. The method was used to design a wideband monopole antenna with application in higher cellular, WLAN …
Resolution Investigation Of A Ratiometric Wavelength Measurement System, Qian Wang, Ginu Rajan, Pengfei Wang, Gerald Farrell
Resolution Investigation Of A Ratiometric Wavelength Measurement System, Qian Wang, Ginu Rajan, Pengfei Wang, Gerald Farrell
Articles
Theoretical analysis and experimental investigations are presented on the resolution of a ratiometric wavelength measurement system. Theoretical modeling indicates that the resolution of a ratiometric wavelength measurement system is determined by the signal-to-noise ratio of the input signal and the noise of the photodetectors associated with optical-to-electronic conversion. For experimental verification, a ratiometric system employing a macrobending standard single-mode fiber is developed and corresponding results are in good agreement with the theoretical prediction.
Video Frame Differentiation For Streamed Multimedia Over Heavilty Loaded Ieee 802.11e Wlan Using Txop, Nicola Cranley, Mark Davis
Video Frame Differentiation For Streamed Multimedia Over Heavilty Loaded Ieee 802.11e Wlan Using Txop, Nicola Cranley, Mark Davis
Conference papers
In this paper we perform an experimental investigation of using video frame differentiation in conjunction with the TXOP facility to enhance the transmission of parallel multimedia streaming sessions in IEEE 802.11e. The delay constraints associated with the audio and video streams that comprise a multimedia session pose the greatest challenge since real-time multimedia is particularly sensitive to delay as the packets require a strict bounded end-to-end delay. Video streaming applications are considered to be bursty. This burstiness is due to the frame rate of vide., the intrinsic hierarchical structure of the constituent video frame types. The TXOP facility is particularly …
Experimental Tuning Of The Aifsn Parameter To Prioritize Voice Over Data Transmission In 802.11e Wlan Networks, Miroslaw Narbutt, Mark Davis
Experimental Tuning Of The Aifsn Parameter To Prioritize Voice Over Data Transmission In 802.11e Wlan Networks, Miroslaw Narbutt, Mark Davis
Conference papers
In this paper we experimentally study the impact of one EDCA parameter, namely AIFSN on a mixed voice/data wireless transmission. In particular we investigate how the tuning of this parameter affects both the voice transmission quality and background data throughput. We predict end-to-end voice transmission quality from time varying transmission impairements using the latest Appendix to the ITU-T E-model. Our experiemental results show that the tuning of the AIFSN parameter can successfully prioritize voice transmission over data in a real 802.11e network. To the best of our knowledge this is the first experimental investigation on tuning of MAC layer parameters …
Experimental Tuning Of Aifsn And Cwmin Parameters To Prioritize Voice Over Data Transmission In 802.11e Wlan Networks, Miroslaw Narbutt, Mark Davis
Experimental Tuning Of Aifsn And Cwmin Parameters To Prioritize Voice Over Data Transmission In 802.11e Wlan Networks, Miroslaw Narbutt, Mark Davis
Conference papers
In this paper we experimentally study the impact of two EDCA parameters, namely AIFSN and CWmin, on a mixed voice/data wireless transmission. In particular we investigate how the tuning of these parameters affects both the voice transmission quality and background data throughput. We predict end-to-end voice transmission quality from time varying transmission impairments using the latest Appendix to the ITU-T E-model. Our experimental results show that the tuning of the EDCA parameters can be used to successfully prioritize voice transmission over data in real 802.11e networks. We also demonstrate that the AIFSN parameter more effectively protects voice calls against background …
An Experimental Investigation Of Parallel Multimedia Streams Over Ieee 802.11e Wlan Networks Using Txop, Nicola Cranley, Tanmoy Debnath, Mark Davis
An Experimental Investigation Of Parallel Multimedia Streams Over Ieee 802.11e Wlan Networks Using Txop, Nicola Cranley, Tanmoy Debnath, Mark Davis
Conference papers
In this paper we perform an experimental investigation of the IEEE 802.11 TXOP facility to enhance the transmission of parallel multimedia streaming sessions through efficient bandwidth reservation and explicitly consider both the audio and video streams. The delay constraints associated with the audio and video streams that comprise a multimedia session pose the greatest challenge since real-time multimedia is particularly sensitive to delay as the packets require a strict bounded end-to-end delay. We show how the TXOPlimit parameter can be efficiently dimensioned to reduce the tranmission delay for the video frames. Due to tis frame-based nature, video applications are considered …
Rare: Resource Aware Routing For Mesh, Karol Kowalik, Brian Keegan, Mark Davis
Rare: Resource Aware Routing For Mesh, Karol Kowalik, Brian Keegan, Mark Davis
Conference papers
An important element of any routing protocol used for Wireless Mesh Networks (WMNs) is the link cost function used to represent the radio link characteristic. The majority of the routing protocols for WMNs attempt to accurately characterise the radio link quality by constructing the link cost function from the measurements obtained using active probing techniques, which introduces overhead. In this paper we propose a new approach called Resource Aware Routing for mEsh (RARE) which instead employs passive monitoring to gather radio link information. This results in a smaller overhead than the other methods that require active network probing, and is …
Polarization Dependence Of Bend Loss For A Standard Singlemode Fiber, Qian Wang, Ginu Rajan, Pengfei Wang, Gerald Farrell
Polarization Dependence Of Bend Loss For A Standard Singlemode Fiber, Qian Wang, Ginu Rajan, Pengfei Wang, Gerald Farrell
Articles
Polarization dependence of bend loss caused by the polymer coating layer for a standard singlemode fiber (SMF28) is investigated theoretically and experimentally. Bend loss for SMF28 for both the TE and TM mode is calculated separately. Normalized polarization dependent loss is proposed for the characterization of the polarization sensitivity of bend loss for different bend radii. Corresponding experimental tests are presented, which agree with the theoretical results. Both the theoretical and experimental results show that the polymer coating layer has a significant influence on the polarization dependence of bend loss.
User Quality Of Experience-Aware Multimedia Streaming Over Wireless Home Area Network, Gabriel-Miro Muntean, Nicola Cranley
User Quality Of Experience-Aware Multimedia Streaming Over Wireless Home Area Network, Gabriel-Miro Muntean, Nicola Cranley
Conference papers
For multimedia streaming over wireless networks, there is a trade-off between the capacity of the wireless links and the end-user perceived-quality, which can be affected by the compression scheme used, content characteristics and adaptation algorithm (if any). In this paper, this trade-off is investigated for streaming various motion content multimedia over an IEEE 802.11b-based Wireless-Home Area Network using the Quality-Oriented Adaptation Scheme (QOAS). QOAS performance is compared to that of a non-adaptive scheme when using MPEG-2 and MPEG-4 encoding in terms of average end-user perceived quality, number of streaming sessions concurrently supported, loss rate, delay, jitter and total throughput. Simulation …
Discontinuous Change In The Smectic Layer Thickness In Ferrielectric Liquid Crystals, V. P. Panov, J. K. Vij, Yuri Panarin, C. Blanc, V. Lorman, J. W. Goodby
Discontinuous Change In The Smectic Layer Thickness In Ferrielectric Liquid Crystals, V. P. Panov, J. K. Vij, Yuri Panarin, C. Blanc, V. Lorman, J. W. Goodby
Articles
The temperature dependence of the thickness of thick free-standing films is studied using a high-resolution film thickness measurement technique. A small discontinuity in the temperature dependence of the smectic layer thickness at every phase transition between ferro-, ferri-, and antiferroelectric phases is observed. We show that the major contribution to it arises from a change in the smectic tilt angle.
Macrobending Fiber Loss Filter, Ratiometric Wavelength Measurement And Application, Qian Wang, Ginu Rajan, Gerald Farrell, Pengfei Wang, Yuliya Semenova, Thomas Freir
Macrobending Fiber Loss Filter, Ratiometric Wavelength Measurement And Application, Qian Wang, Ginu Rajan, Gerald Farrell, Pengfei Wang, Yuliya Semenova, Thomas Freir
Articles
A macrobending standard single-mode fibre (SMF28) is optimized as an edge filter, with the optimal bending radius and length determined according to the bend loss and polarization sensitivity of the bending fibre. An all-fibre ratiometric wavelength system is built and calibrated. The system's accuracy and resolution is discussed with the influence of noise of input signal and photodetectors. Finally, the ratiometric system is employed for the demodulation of FBG strain sensing.
A Brief Introduction To Speech Synthesis And Voice Modification, Alan O'Cinneide, David Dorran, Mikel Gainza
A Brief Introduction To Speech Synthesis And Voice Modification, Alan O'Cinneide, David Dorran, Mikel Gainza
Conference papers
For both engineers and linguists, the computer synthesis of natural speech is an objective that would provide many useful applications to human-computer interaction, including the realm of electro-acoustic music. The purpose of this paper is to introduce the area of speech synthesis by providing an overview of the three main methods of computer speech synthesis; namely concatenative, articulatory and formant syntheses. Some aspects of the current state of the technology are illuminated and the final section will explain the author’s motivation and current research approach to the field of voice modification.
Blind Source Separation And Automatic Transcription Of Music Using Tensor Decompositions, Derry Fitzgerald
Blind Source Separation And Automatic Transcription Of Music Using Tensor Decompositions, Derry Fitzgerald
Conference papers
Recent advances in the use of tensor decompositions for the analysis of music are described. In particular, the use of such decompositions for sound source separation and the automatic transcription of music are explored.
The Role Of Spontaneous Polarization And The Thickness Of Alignment Layers On The V-Shaped Switching In Flc Cells, V. Manjuladevi, J.K. Vij, Yuri Panarin
The Role Of Spontaneous Polarization And The Thickness Of Alignment Layers On The V-Shaped Switching In Flc Cells, V. Manjuladevi, J.K. Vij, Yuri Panarin
Articles
Ferroelectric liquid crystal mixtures with the various values of spontaneous polarizations were prepared, and the substrates were coated with different thicknesses of aligning agent. The frequency dependence of the electrooptic response of these materials in cells with various thickness of alignment layers has been measured. The coercive voltage as well as the contrast ratios are calculated. Our results support the ‘‘electrostatic model’’, according to which both the value of spontaneous polarization and the thickness of the alignment layer play important roles in the V-shaped switching.
An Optimized Macrobending Fiber Based Edge Filter, Pengfei Wang, Gerald Farrell, Qian Wang, Ginu Rajan
An Optimized Macrobending Fiber Based Edge Filter, Pengfei Wang, Gerald Farrell, Qian Wang, Ginu Rajan
Articles
An optimized all-fiber edge filter is developed, based on a one-turn macrobending bare fiber structure. The discrimination range is 16.32 dB over a wavelength range from 1500 to 1600 nm, which can be employed for wavelength measurement applications. It offers a simpler structure compared to the previously developed macrobending fiber loss edge filters, without an increase in the polarization-dependent loss.
Small Patch/Slot Antenna With 53% Input Impedance Bandwidth, Xiulong Bao, Max Ammann
Small Patch/Slot Antenna With 53% Input Impedance Bandwidth, Xiulong Bao, Max Ammann
Articles
A small microstrip patch/slot antenna, which achieves a very large bandwidth on a relatively thin substrate (about 0.01lambda0), is presented. The performance is achieved by employing a combination of annular-ring loading on the patch radiator and the use of a crossed-slot for miniaturisation. An additional ring-slot in the ground plane is used to produce the wideband characteristics of the antenna. Simulated and measured results indicate that a 53% fractional impedance bandwidth is achieved with respect to the centre frequency of 1.409 GHz and the size of the antenna is reduced by 50% compared to the conventional circular patch antenna with …
Effect Of Polarisation-Dependent Loss On The Performance Accuracy Of A Ratiometric Wavelength Measurement System, Ginu Rajan, Qian Wang, Yuliya Semenova, Gerald Farrell, Pengfei Wang
Effect Of Polarisation-Dependent Loss On The Performance Accuracy Of A Ratiometric Wavelength Measurement System, Ginu Rajan, Qian Wang, Yuliya Semenova, Gerald Farrell, Pengfei Wang
Articles
The polarisation-dependent loss (PDL) of a ratiometric wavelength measurement system and its influence on system's accuracy are investigated theoretically and experimentally. The PDL of a ratiometric system and the corresponding power ratio fluctuation is modelled, from which the accuracy of the measured wavelength can be estimated. An all-fibre wavelength measurement system is built to allow comparison of modelled and actual results. The measured ratio variation lies within the estimated limits. The measured wavelength error reaches about 1.41 plusmn 0.09 nm at 1550 nm in the demonstrated example (with an edge filter of average slope 0.22 dB/nm), which indicates the significant …
A Method To Measure Reference Strain In Fbg Strain Sensor Interrogation System Involving Actuators, Ginu Rajan, Yuliya Semenova, Qian Wang, Gerald Farrell, Pengfei Wang
A Method To Measure Reference Strain In Fbg Strain Sensor Interrogation System Involving Actuators, Ginu Rajan, Yuliya Semenova, Qian Wang, Gerald Farrell, Pengfei Wang
Articles
A method for reference strain measurement for FBG strain sensor in the testing stage while applying strain using actuators like piezo translators or micro screw is introduced. Unlike conventional methods of surface mounting, in our method the strain gauge is affixed directly to the optical fibre, which allows it to use with systems where the strain is applied directly using actuators while testing the FBG sensing system. Different bonding techniques were tested and a comparison with the results from calculated values are presented. Since the contact area between the fibre and strain gauge is very small a corrected gauge factor …
A Novel Wideband Semi-Planar Miniaturized Antenna, Giuseppe Ruvio, Max Ammann
A Novel Wideband Semi-Planar Miniaturized Antenna, Giuseppe Ruvio, Max Ammann
Articles
A semi-planar miniaturized antenna which operates over the FCC allocated UWB spectrum is presented. The small antenna comprises a folded conducting element connected to a printed section. Several solutions are introduced which create different current paths increasing the effective dimensions of the antenna. The antenna is examined for the stand-alone case and for the antenna mounted in various locations on a larger handset-type groundplane. The impedance and radiation characteristics show a relative independence of the groundplane size and the antenna location on it. The proposed antenna is a valuable candidate for handset applications due to its compactness. The proposed antenna …
Making Olsr Aware Of Resources, Karol Kowalik, Brian Keegan, Mark Davis
Making Olsr Aware Of Resources, Karol Kowalik, Brian Keegan, Mark Davis
Conference papers
An important element of any routing protocol used for Wireless Mesh Networks (WMNs) is the link cost function used to represent the radio link characteristic. The majority of the routing protocols for WMNs attempt to accurately characterise the radio link quality by constructing the link cost function from the measurements obtained using active probing techniques which introduces overhead. In this paper we present a modified version of the Optimized Link State Routing (OLSR) protocol which uses the link cost function values provided the Resource Aware Routing for mEsh (RARE) module which employs passive monitoring to gather radio link information. This …
Investigation On Proximity-Coupled Microstrip Integrated Pv Antenna, Maria Roo Ons, S. Shynu, Max Ammann, Sarah Mccormack, Brian Norton
Investigation On Proximity-Coupled Microstrip Integrated Pv Antenna, Maria Roo Ons, S. Shynu, Max Ammann, Sarah Mccormack, Brian Norton
Conference papers
The use of polycrystalline silicon solar cells (156 times156 mm) as a groundplane for a proximity-coupled microstrip square patch antenna (30 times 30 mm) is investigated. Four different models that arise from the different possible positions of the cell with respect to patch, were simulated, fabricated and compared to an ideal PEC ground plane antenna of the same size. It was found that the use of the solar cell as ground plane is feasible, yielding similar impedance bandwidth (around 4%, 3.5% for the PEC) with reasonable gain. The feasibility of using poly-crystalline solar cells as a ground plane, instead of …
Investigation On Miniature Wideband Patch Antenna For Portable Wireless And Cellular Applications, Xiulong Bao, Max Ammann
Investigation On Miniature Wideband Patch Antenna For Portable Wireless And Cellular Applications, Xiulong Bao, Max Ammann
Conference papers
A low-profile miniature antenna with very wide bandwidth is proposed for emerging multimode devices. It comprises a small circular patch antenna loaded by a metallic annular-ring and located on a laminate with a slotted ground plane. The design achieves a very compact low-profile antenna with broadband performance. By optimizing the parameters of the annular-ring patch antenna, very broadband characteristics can be obtained. The measured results show that the antenna achieves a 10 dB return loss from 1.383 GHz to 2.210 GHz, (827 MHz) ie about 47% with respect to the centre frequency 1.796 GHz. The measured results are in good …