A Multiband Low Noise Amplifier for Software Defined Radio Using Switchable Active Shunt Feedback Input Matching

Radio frequency (RF) receivers are the key front-end blocks in wireless devices such as smartphones, pagers, PDAs etc. An important block of the RF receiver is the Low-noise amplifier. It’s function is to amplify with little noise addition, the RF signal received at the atenna. Modern wireless devices for example the smartphone, incorporates multiple functionalities supported by various RF standards- GPS, Bluetooth, Wifi, GSM etc. Thus, the current trend in the wireless technology is to integrate radio receivers for each RF standard into a single system-on-chip (SoC) in order to reduce cost and area of the devices. In view of this, multiband RF receivers have been developed which feature multiband LNAs. This thesis presents the design and implementation of a multiband LNA for Software Defined Radio Applications. In this thesis, basic radio-frequency concepts are discussed which is followed by a discussion of pros and cons of various multistandard low-noise amplifier topologies. This is then followed by the design of the proposed reconfigurable LNA. The LNA is designed and fabricated in IBM 0.18um CMOS technology. It is made up of dual LC resonant tanks, one to switch between 5.2GHz and 3.5GHz frequency bands and the other, to switch between 2.4GHz and 1.8GHz bands. The input matching of the LNA is achieved using a switchable shunt active feedback network. The LNA achieves S21 of between 10.1dB and 13.43dB. It achieves an input matching (S11) between -13.44 dB and -11.97 dB. The noise figure measured ranges from 2.8 dB to 4.3 dB. The LNA also achieves an IIP3 from -7.12 dBm to -3.45 dBm at 50 MHz offset. The power consumption ranges from 7 mW to 7.2 mW

WELCOMING THE SEMICONDUCTOR INDUSTRY IN GHANA: CHALLENGES AND RECOMMENDATIONS – A CASE STUDY

The Semiconductor Industry is one industry that has been driving technological innovations for decades since its birth in the USA. Semiconductors form the building blocks of a wide array of consumer, medical and industrial electronics. The growth of many economies in the world can be attributed to the growth in the semiconductor industry in such countries. The global semiconductor industry consists of companies in the USA, South Korea, Taiwan, China, and the European Union. However, the semiconductor industry has no presence in the African region, in Ghana to be specific. This work investigates some challenges associated with the establishment of the semiconductor industry in Ghana, including challenges from basic research and development to manufacturing and marketing. The paper also highlights some recommendations which are key in laying the foundation for the entry of the industry in Ghana, including the provision of tax incentives, training of personnel, etc

WELCOMING THE SEMICONDUCTOR INDUSTRY IN GHANA: CHALLENGES AND RECOMMENDATIONS – A CASE STUDY

The Semiconductor Industry is one industry that has been driving technological innovations for decades since its birth in the USA. Semiconductors form the building blocks of a wide array of consumer, medical and industrial electronics. The growth of many economies in the world can be attributed to the growth in the semiconductor industry in such countries. The global semiconductor industry consists of companies in the USA, South Korea, Taiwan, China, and the European Union. However, the semiconductor industry has no presence in the African region, in Ghana to be specific. This work investigates some challenges associated with the establishment of the semiconductor industry in Ghana, including challenges from basic research and development to manufacturing and marketing. The paper also highlights some recommendations which are key in laying the foundation for the entry of the industry in Ghana, including the provision of tax incentives, training of personnel, etc

Exposing Students to Engineering in Society

Engineering and for that matter engineering training is pivotal in solving problems that confront societies. This paper introduces academia to a course named Engineering in Society run at the College of Engineering of the Kwame Nkrumah University of Science and Technology, Kumasi, Ghana. The paper also reports on an assessment of the course content, mode of delivery and impacts, and recommends improvements to enhance its learning outcomes. The impact assessment was done through the administration of questionnaires to four hundred and thirty-seven current and immediate past students of the College’s Department of Electrical and Electronic Engineering. The respondents were students in the second, third and fourth years of the BSc Electrical and Electronic Engineering programme as well as its immediate past alumni. The results of the impact assessment show that over 85% of the respondents from the various categories consider the course to be essential for their career development. Between 56.76% and 79.38% of respondents from the various groups are satisfied with the mode of delivery of the course. Not less than 69% of the responds agree to the attainment of at least one of the learning outcomes of the course. The respondents consider the community project component of the course as the most impactful. The study has revealed an increasing trend of students contracting others to do their community projects for them as well as an increasing trend in plagiarism of submitted reports. Among others, the study recommends some revision of the course content and mode of delivery to maximize the impact of the course. Additionally, the university should do away with the submission of reports in printed copy and rather migrate to online submission of reports, with plagiarism checks. The course, with the suggestions made, is recommended for adoption by engineering training institutions

Intelligent Miniature Circuit Breaker

The traditional electrical distribution panel (or breaker panel) is a system that divides the main electrical power feed and distributes them to subsidiary circuits whiles providing a protective mechanism via the use of miniature circuit breakers, residual current devices, etc. The conventional panel distributes electrical power alright but the system does not make provision for any form of real time monitoring and feedback of power consumption levels in the home. This paper presents a design of a miniature circuit breaker distribution panel integrated with other electronic devices which helps achieve real time monitoring of power consumption and also automatically trips the circuit if there is a fault and reconnects the circuit if the fault is cleared to ensure little to no interruption in electricity to appliances

An alternative design and implementation of a solid state on-load tap changer

Power quality and reliability are of great importance in the modern world, whether it be the power generated by the power utilities or the power consumed by the customer respectively. They need these supplies to be at its optimum value so that the cost is effective, and the safety of devices assured otherwise problems such as overvoltage, under-voltage, and voltage sags caused by disturbances in the power supply could be disastrous. On-load tap changers (OLTC) have therefore been used since the inception of electrical engineering. The main function of the OLTC is to change the turns of the transformer winding so that the voltage variations are limited without interrupting the secondary current.The major idea is that the electronic switches and other smart systems provide more controllability during the tap changing process, unlike mechanical switches.This paper presents an alternative design and implementation of a low-cost solid-state OLTC and employs a control strategy that is microcontroller-based, ensuring the desired flexibility and controllability required in programming the control algorithms.It eliminates the limitations of both mechanical and hybrid OLTCs (arcing, slow response time, losses) and is user-friendly (provides an effective communication medium). Voltage regulation is achieved by varying the turns of the transformer winding whiles it is energized, supplying load current and with the tap selection carried out on the primary side. Therefore, this approach provides a less expensive system but ensures the efficiency and reliability of voltage regulation