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The evolution of Wireless Body Area Network (WBAN) is made possible due to the rapid growth of wireless network and constant miniaturization of electrical devices. However, designing an antenna that is suitable for WBAN applications is challenging as the antenna should has compact size, in addition to the ability to endure low power loss during transmission and has robust communication link. Thus, a miniaturized wearable Dielectric Resonator Antenna (DRA) capable of radiating circularly polarized (CP) wave is designed. The antenna designing is done by using CST software. A total of 140 simulations is simulated in order to obtain the desired results. The DRA is used, together with conformal copper strips and miniaturized copper ground plane. The single point fed antenna is excited by a unique capital F-shaped conformal copper strips. The CP DRA offers a simulated Axial Ratio bandwidth below 3dB of ~23.85%, which is much greater than what has been reported in the previous work, with bandwidth of S11 below −10dB ~ 16.066%. In addition, the antenna designed in this research project managed to achieve an overlapped bandwidth of ~14.10% (6.9GHz – 7.94GHz). A prototype antenna is fabricated to validate the simulation result. Thus, the antenna design in this research will be helpful towards the evolution of the WBAN.

The e-CALLISTO system is a worldwide network that aims to observe solar radio emission for astronomical science. CALLISTO instruments have been deployed worldwide in various locations that together can provide continuous observation of the solar radio spectrum for 24 h per day year-round. Malaysia-UKM is a strategic equatorial location and can observe the Sun 12 h per day. This paper gives an overview of the spectrum allocation for radio astronomy, which falls in the specified operating frequency band of the CALLISTO spectrometer. The radio astronomy bands are analyzed at the Malaysia-UKM station according to the International Telecommunication Union recommendations. Some observational results are also presented in this paper.

Array antenna has been utilized in many radio telescope systems, especially for low frequency transient observation, to increase their resolving power. In this paper, a new method to determine the maximum resolving power of an array radio telescope based on the single antenna beamwidth is proposed. The method is derived from theoretical calculations combined with simulations. Statistical result shows that the equation inherits a standard error of 0.99, and hence is suitable to be used for rough calculation in determining an array maximum resolving power. It also can be used to estimate the maximum resolving power of an interferometer system with a slightly lower precision at very long baseline.

Dipole-based antenna has been widely used as the front end section of a radio telescope system, especially for low frequency observation. In this paper, a new method on designing dipole-based antenna for transient radio telescope system is presented. The method consists of three equations which were derived from statistical approach, by utilizing data from many antenna designs for different operating frequencies. Some of the designs have been constructed and measured, with frequency peak error down to 0.7%. These antennas have been utilized in some radio telescope systems, operated at National Space Center of Malaysia for solar monitoring.

The Compound Astronomical Low-Cost Low-Frequency Instrument for Spectroscopy and Transportable Observatory (CALLISTO) is a worldwide network of radio spectrometers designed for 24-hour solar observation. It is a collaboration among the Swiss Federal Institute of Technology Zurich and numerous local host institutes, spread out around the world. This paper presents an overview of the CALLISTO spectrometer system at the Universiti Kebangsaan Malaysia (UKM). The ?Malaysia-UKM? station is installed inside the campus area, at the Permata Pintar School building. In particular, this paper explains the details of the instrument's setup, and reports some of the data observed from this station. The realtime data are available from the e-CALLISTO International Network of Solar Radio Spectrometers.

Low-frequency radio astronomy has become a fascinating research area in the field of astronomy, including on its instrumentation development. In this paper, a multiband VHF antenna for low-frequency transient radio telescope is developed. The multiband has been achieved by combining V-shape half-wavelength dipole, traps, and parasitic elements. Measurement result shows that the antenna can work properly in three different frequencies designated by International Telecommunication Union (ITU) for radio astronomical purposes.

Antenna is one of the important subsystem components in a radio telescope system. In this paper, analysis on the effect of parasitic element on 408 MHz antenna in a radio telescope system is presented. Higher gain up to 10.24 dBi with reduction on beamwidth size has been achieved by optimizing the position of parasitic element relative to the driven element. The proposed antenna is suitable to be utilized in a transient radio telescope array.

The dipole-based antenna has been employed in many radio telescope systems. By utilizing this type of antenna, the possibility to conduct all sky monitoring and high spatial resolution observation in the same time can be provided. In this research, a new dipole-based antenna system will be developed for 21cm line observation. The dipole-based antenna is optimized in terms of standing wave ratio (SWR), gain and beamwidth. Initial results show a good achievement on SWR level, down to 1.005.

Dipole-based antenna has been used in many radio telescope systems, especially for low frequency astronomical observation. In this paper, analysis on beamwidth and gain of V-shape dipole-based antenna for different applications in radio astronomy observation is presented. Parameters to obtain wide and narrow field of view, up to 134°, down to 94°, are achieved with simple structures. Possibility to trade the beamwidth and gain off with higher sensitivity is also provided as low standing wave ratio down to 1.008 has been achieved. The results show different structures suitable for different applications in radio astronomy.

Design and development of antenna array for low frequency radio telescope has become one fascinating research in the field of Astronomy. In this research, optimization of two-element multiband antenna array for low-frequency transient radio telescope is presented. Narrow beamwidth down to 14 degrees has been achieved with maximum gain up to 12.31 dBi. The array is suitable to be used in a radio telescope system for solar and transient object monitoring.

Development of antenna for a radio telescope system has become a fascinating research area in the field of radio astronomy. In this paper, a design of compact multiband VHF antenna for a transient radio telescope system is proposed. The multiband has been achieved by combining V-shape half-wavelength dipole, traps and parasitic elements. Return losses of about −12.45 dB, −25.15 dB and −29.42 dB are obtained at three different frequencies, where the maximum gains are achieved at zenith direction for all operating frequencies. The proposed antenna is suitable to be used in a transient radio telescope which is operated in urban centers.