Seyi Stephen Olokede

Electrodynamic Study of a Novel Microstrip Ring Based on Finite Integral Technique Numerical Computational Code

We present a novel microstrip ring resonator (MRR) excited by a transmission line. The MRR is capable of controlling signal propagation along the peripheral of the resonator such that it is able to prohibit signal propagation within the vicinity of the narrow band closed to the target resonant, so long the magnetic component of the electromagnetic (EM) field is polarized with respect to the ring axis. The magnetic fields invariably induced current at the MRR loops via the distributed capacitance between the rings at target frequency, to ensure the frequency-selective characteristics. The selectivity behaviour is dependent on the degree of the induced current in the ring loop at the frequency under consideration can be explained by the induced current loops in the rings at resonance. We therefore investigate the electrodynamics propagation mechanism of this novel MRR to leverage on its frequency-selective behaviour to evolve miniaturized passive resonators.

Spatial Array of Microwave Sensors for IoT-Based Wireless Connectivity

Spatial array of microwave sensors for IoT-based wireless connectivity is presented. The traditional challenges of poor input impedance matching associated with small antenna are analytically characterized using the many available formulae based on a novel 2 × 2 excitation network. Alternative microwave sensor solution designed at originally known low data throughput IEEE 802.11x standard was previously investigated to support multichannel bandwidth capacity, and now examined for robust link budget to provide complementary leverage for IoT-based applications.

A Corporate Feed Network Optimization for Performance Enhancement

Big data technology sustainability is contingent on the availability of interconnections of large-scale, ultra-high-speed, densely integrated big data heterogeneous server platforms. For highly densified servers to be attainable, semiconductor technologies upon which these servers are predicated must further be miniaturized. It is recently not uncommon to implement band gap reduction engineering of SiGe HBT in a bid to attain highly densified integrated circuit for large-scale servers. Unfortunately, the parasitic effects become significant, in particular as these integrated circuits are targeted for high frequency of operations due to the interconnection links between the chip and the transceivers. Insertion loss |S21| becomes considerable, and both the signal level as well as noise figure depreciate substantially as a result. In this work, therefore, we investigate the extent of parasitic effect to wit performance degradation, and further to optimize the parasitics for performance enhancement.

Parasitic Effect on Reduced Latency of SoC-Based Big Data

Big data technology sustainability is contingent on the availability of interconnections of large scale, ultra-high speed, densely integrated big data heterogeneous server platforms. For highly densified servers to be attainable, semiconductors technologies upon which these servers are predicated must further be miniaturized. It is recently not uncommon to implement band gap reduction engineering of SiGe HBT in a bid to attain highly densified integrated circuit for large-scale servers. Unfortunately, the parasitic effects become significant, in particular as these integrated circuits are targeted for high frequency of operations due to the interconnections links between the chip and the transceivers. Insertion loss |S21| becomes considerable, and both the signal level as well as noise figure depreciate substantially as a result. In this work, therefore, we investigate the parasitic effect of interconnections on the roundtrip latency of system-on-chip (SoC).

A Corporate Network-Fed Quasi-lumped Resonator Antenna Array

A new class of antenna is presented. It consists of an interdigital capacitor in parallel with a straight strip inductor. The proposed antenna is fed through a new corporate feed network. The configurations designed, fabricated, and measured include 8 × 1 and 8 × 2. Each resonator is fed at the non-radiating end with a view to achieving higher gain and better performance. The performance profile of the array antenna, including the reflection coefficient and radiation patterns, is investigated and presented. Reasonable measured gains of 12.8 and 16.9 dBi are obtained for 8 × 1 and 8 × 2 configurations, respectively. The size of each element of the array is 5.8 × 5.6 mm2, which makes it a potential candidate for wireless communication applications.

Miniaturized Microwave Sensor for Internet of Things Wireless Connectivity

A miniaturized microwave sensor for internet of things (IoTs) is presented. The proposed sensor though a periodic structure exhibits two intrinsic resonances, namely the spatial wavelength due to its periodic geometric structure and the radiation wavelength due to applied voltage source to the microwave sensor. The wavelength difference between the spatial and radiation wavelengths is employed for the sensing based on the electrical impedance tomography of the sensed material. The miniaturized capability of the proposed sensor is investigated based on some available formulae using Matlab code for parameter extraction, and also with finite integration technique electromagnetic (EM) codes. A proof-of-concept prototyped sensor is fabricated on a printed circuit microwave laminate board in order to validate the miniaturized capability of the proposed sensor. Findings indicate a superior impedance match, substantial impedance bandwidth, robust gain, and cost-effectiveness, compared to AoC/AiPs with associated losses due to the silicon substrate.

Design of a Quasi-Lumped Resonator Antenna Array Based on a Novel Optimized Corporate Network Feed

A corporate network-fed quasi-lumped resonator antenna array is presented. A new class of patch antennas comprising of an interdigital capacitor in parallel with a straight strip inductor is employed as radiators, whereas an optimized corporate feed network is designed to couple excitation power to the radiating elements. The proposed radiating elements rely on the long but folded capacitance occurring between the interdigit gap, thus ensuring the miniaturization of the passives. The feed network has also been optimized for compactness and power propagation efficiency with minimum transmission losses. An 8 × 1 and an 8 × 2 are prototyped and investigated using the finite integration technique numerical code. The resulting design is litographically etched on a Roger duroid microwave laminate and subsequently measured. Findings indicate that the resulting design is compact in terms of estate area occupancy and demonstrates reasonable radiation efficiency.

Electromagnetic Interference and Discontinuity Effects of Interconnections on Big Data Performance of Integrated Circuits

An antenna-in-package solution has recently been the ultimate technology offering innovation and perhaps the most highly integrated radio miniaturization surface-mounted chipset device for short-range, high-speed, high-gain, and large-scale big data hyper-performance server platforms. Electromagnetic interference (EMI) arises as a result of discontinuity of the interconnections between the antenna and the integrated circuit (IC) chips, which limits their efficiency considerably, as it increases the mutual coupling and initiates and propagates surface waves, thus limiting the radiation efficiency in particular at the far-field. The backplanes, on which the IC boards containing data communication chips and processors are densely installed, are interconnected with high-speed integrated transceiver circuits using wire traces and connectors. As a result, transmission losses become considerable, in particular for backplanes operating at transfer speeds greater than 10 Gbps. In effect, the signal distortion becomes so significant that accurate data transmission without distortion is near impossible. Techniques to ameliorate the drawbacks of the side effects of parasitics are investigated in this chapter. Existing solutions to mitigate such effects are assessed to determine the extent of their efficacy. Alternative coupling techniques are examined. The effects of grounding, filtering, guard rings, shielding and decoupling are studied. The implication of process technology in eliminating EMI is also examined.

A novel-fed fixed frequency-source dielectric resonator for frequency stability-dependent applications

A simple and novel microstrip-fed dielectric resonator (DR) as fixed frequency source is proposed. The feed mechanism consists of three microstrip line sections, each of a width approximately equal to its characteristic impedance. The DR located at the centre of the grounded laminate Roger RO4003C Duroid microwave board of size 18 × 18 sq. mm, with a substrate height of 0.813 mm, dielectric constant εr = 3.38 ± 0.05, and a metallization of 35 μm is excited by these microstrip lines such that port 1 and 2 are oppositely edges-coupled to the DR in a balanced parallel arrangement, whereas, the third microstrip line is orthogonal to the microstrip feed line excited by port 2. Each of the feed line are located at a coupling space (β) of 0.24mm away from the DR, whereas, the third orthogonal microstrip line is capacitively coupled through the excitation of port 1 and 2. Both the measured and numerical results agreed reasonably.

Efficient coupling excitation mechanism for planar array antennas

When proximity coupling via coaxial feed probe is employed to excite planar array antenna, efficiency of such excitation could be compromised and the consequences could be severe for large arrays. The centre-excitation by a single coaxial probe to a planar array could be an over-kill of the excitation mechanism for large array. We therefore investigate the efficacy of a 2 × 2 excitation sources via a 4 coaxial feed probe network. We examine the strength of excitation energy by each source and predict the radiation map based on each source to determine the radiation boundary per a source. We then determine the percentage of the excitation distribution per source that are scattered using the scattering parameter.