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This paper presents the experimental research on the influence of clock synchronisation in a multi-transceiver radar system in terms of phase noise and stability of the clock source. The work involves an implementation of a clock distribution method and discusses the experimental results. The TIGER-3 radar is being developed as an "all digital" radar with 20 integrated digital transceivers, each operating at 2.4kW of nominal power. Accurate coordination of all 20 transceivers is essential for generation of transmit signals, collection and merging of receive data to form a standard SuperDARN data set. Therefore, the system clock frequency must be highly stable and be tightly synchronised. In order to achieve this, a clock synchronisation method to coordinate the operation of entire system using a highly stable, accurate common clock source distributed to the transceivers is proposed. To improve noise immunity, differential signals are used. To further enhance the electromagnetic interference (EMI) immunity of the clock system, magnetic circuitry is employed. Moreover, the FPGA clocking features including Digital Clock Managers (DCMs) and PhaseLocked Loops (PLLs) available on the Xilinx Virtex-5 devices are used to correct and recover the received clock. Test results show that the clock system has excellent noise immunity allowing the radar system to perform at its full power.

Wildlife tracking is used to acquire information on the movement, behaviour and survival of animals in their natural habitat for a wide range of ecological questions. However, tracking and monitoring free-ranging animals in the field is typically labour-intensive and particularly difficult in species that are small, cryptic, or hard to re-capture. In this paper, we describe and evaluate an Internet-of-Things (IoT)-based tracking system which automatically logs detected passive RFID tags and uploads them to the cloud. This system was successfully evaluated with 90 sensor modules deployed in a 30 ha wildlife sanctuary to monitor a small nocturnal mammal of less than 20 g in body size.

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The Tasman International Geospace Environment Radars (TIGER) form part of an international network of similar HF radars called Super Dual Auroral Radar Network (SuperDARN) which explore the impact of solar disturbances on Earth. These radars utilise an Auto Correlation Function (ACF) to measure the changing phase of the ACF between lag times to determine the Doppler frequency and the target velocity. With the development of TIGER-3, an all digital radar platform, a novel method of determining target velocities has been proposed. In the proposed method, a comparison of the transmit and receive signal magnitude spectrums is performed to determine the Spectrum Difference Function (SDF). The gradient of SDF in the vicinity of the carrier frequency is calculated, from this value the Doppler Frequency Shift f d can be deduced. The result is then multiplied by a precalculated Scale Factor which is necessary to compensate for the systematic error due to the method. This paper will address all the factors which have influence on the value of Scale Factor, therefore minimize the error associated with the process of calculating Scale Factor.