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Radio astronomy receiver development is focusing on increasing the field of view and bandwidth in tandem with the exponential increase in data volumes permitted by signal processing. We present recent receiver and signal processing developments from CSIRO and FAST.

Five-hundred-meter Aperture Spherical radio Telescope (FAST) is a Chinese mega-science project to build the largest single dish radio telescope in Guizhou province, Southwest China. The construction of FAST will involve many kinds of analog and digital electrical equipments. The electrical equipments are potential threat to radio observation due to its ElectroMagnetic Interference (EMI) emission. The EMI should be safely shielded when FAST telescope operates. The shielding effectiveness of large shielding enclosures can be tested with two log periodic antennas, signal generator and spectrum analyzer. It is not suitable to test small shielding enclosure for that is not possible to put big antenna and signal generator inside. In this paper, an effective shielding effectiveness measurement system for the small shielding enclosure is introduced. This measurement system uses a frequency synthesizer of Valon Technology as signal generator which can measure the shielding effectiveness no more than 100dB in a frequency range of 23–6000MHz. Some of measurement results of shielding effectiveness are also presented.

Five-hundred-meter Aperture Spherical radio Telescope (FAST) is a Chinese mega-science project to build the largest single dish radio telescope in the world. The first light of FAST is expected in September 2016. Due to the high sensitivity of FAST, it is very sensitive to the radio frequency interference coming from the electrical and electronic equipments of telescope itself. In order to assure the realization of the scientific goals of the telescope, the electromagnetic compatibility (EMC) study on FAST at the design and construction stages, has been carried out to decrease the possibility of the interference from the telescope. Several examples, such as EMC designs and measurements for actuator and focus cabin, have been introduced briefly.

Phased array feed (PAF) is an emerging technology which can greatly improve the survey speed of telescopes. As a world-class radio telescope, the Five-hundred-meter Aperture Spherical radio Telescope (FAST) is also trying to enhance its observation capability and open up new scientific studies at several frequency bands by PAFs. At the first partof this paper, the blue print of the FAST PAFs development and corresponding scientific goals are introduced, as well as the progress has been made in these PAFs.

This paper represents a low cost printed Vivaldi antenna at 3–10 GHz bandwidth for Radio telescope Feed system. The idea of this design is to minimize the number of telescope receivers for Square Kilometre Array (SKA) [1]. A minimized tapered slot antenna with a balun feed for receiver systems is proposed. The Vivaldi antenna is design on a relatively low dielectric constant substrate which operates at Ultra-Wideband (UWB). A typical tapered slot antenna is a combination of a wideband balun and a radiator with different tapering shapes such as linear, constant width, exponential and dual exponential. Two feeding configurations are used such as coplanar waveguide (CPW) to slot line transition and microstrip line to slotline transition [2–5]. The antenna modeling is analyzed using two different electromagnetic simulators such as HFSS and CST Microwave Studio. The results are shown that the antenna operates over a wide bandwidth extending from 3.1 to 10.6 GHz with a maximum gain of 7.3 dBi. Stable radiation patterns are observed across the operational bandwidth, with cross-polarization levels below −20 dB. The realized antenna structure occupies a volume of 45 × 45 × 0.5 mm3, and possesses the essential time domain fidelity needed for UWB Radio telescope Feed system applications. A prototype Vivaldi antenna is constructed and measured for validation. The Voltage Standing Wave Ratio (VSWR) of the proposed antenna is verified against the simulated data results, the measured and simulated results are found to be in good agreement. In particular, a good impedance bandwidth matching and stable directional radiation patterns were achieved across the operating frequency range. The combination of design aims and outcomes described in the paper indicates that the proposed antenna can be a suitable candidate for portable RF systems, or possible sensor element in an UWB antenna array application.

This paper presents a novel wideband microstrip band-pass filter for L-band low noise receiver of radio telescope. By introducing a stepped-impedance one-wavelength ring resonator (SORR) into a stepped-impedance half-wavelength resonator (SHR), excellent in-band performance is realized. In order to suppress the harmonic responses of the filter for a wide stop-band, two band-stop sections with asymmetrical π-type structure are designed. A prototype filter having 49.3% of 1-dB and 57.9% of 3-dB fractional bandwidth is fabricated with advantages of compact size, high selectivity and high out-of-band rejection. In the pass-band, return loss is less than −18.8dB and the minimal insertion loss is 0.6 dB.

A loop feed meander-line Antenna (LFMLA) RFID tag on a relatively low dielectric constant substrate operates on the European UHF band 865–868 MHz is presented. The tag modeling is analyzed using two different electromagnetic simulator HFSS and CST. A prototype tag antenna is constructed and measured for validation. The input impedance of the proposed antenna is verified against the simulated data results, the measured and simulated results are found to be in good agreement. The compact size tag antenna shows excellent impedance matching to the typical input impedance of a RFID integrated circuit chip and a significant improvement in reading range up to 5 meters.

Five-hundred-meter Aperture Spherical radio Telescope (FAST) is a Chinese mega-science project to build the largest single dish radio telescope in the world. The first light of FAST is expected in 2016. In order to protect the radio environment for FAST site, the local government has promised to establish a radio quiet zone of 30 km diameter, with the Dawodang depression in Guizhou province as the centre. The legislation of this radio quiet zone is underway.