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Satellite navigation is finding new applications in safety critical systems such as in aviation where it is proposed for approach and landing of aircraft. These new applications place strict requirements regarding position accuracy and system availability. In order to realize these requirements, it is essential to develop robust antenna designs. In this contribution, a multi-band antenna array suitable...
Global navigation satellite system (GNSS) receivers are vulnerable to hostile interference threads, such as jamming and spoofing. A two-stage hybrid interference suppression scheme is proposed to enable mitigating jamming and spoofing ahead of acquisition, separately or simultaneously. An orthogonal complement space of spoofing signals is constructed at the first stage to cancel potential spoofers...
Angle measurement of monopulse is widely used in the angle tracing technique for high precision tracking radar system. This paper analyzes some facts related with precision of angle measurements in monopulse radar, including offset angle of sub-beams, squint angle between target and centerline of main beam, receiver output noise, and target amplitude fluctuation. A new method for angle measurement...
Interplanetary Scintillation (IPS) of compact radio sources at meter to centimeter wavelengths is a useful ground-based method to investigate solar wind. There are 3 technical solutions for IPS observation. At present, each running IPS dedicated telescope represents a solution accordingly. In recent future, a new IPS telescope is proposed to build in China. Therefore, we combined advantages of single...
A novel multi-dimensional noise-shaping method is proposed to extend Δ-Σ modulation to the two-dimensional (2-D) (space, time) case. It uses spatial oversampling to provide another degree of freedom for ADC designers to shape quantization noise when temporal oversampling is limited. The method uses lossless discrete integrators (LDIs) to implement spatial integrators and is suitable for use in microwave...
Digital MIMO receivers featuring digitization at each element are critical for (massive) MIMO applications since they support complex space-time signal processing. However, the lack of spatial selectivity in the analog/RF domain necessitates high-dynamic-range analog-to-digital converters (A/Ds) to accommodate the uneven spatial power distribution, limiting the scale of such MIMO systems. This paper...
The initial phase of the Square Kilometre Array (SKA) [1] is represented by a −10% instrument and construction should start in 2018. SKA 1-Low, a sparse Aperture Array (AA) covering the frequency range 50 to 350 MHz, will be part of this. This instrument will consist of 512 stations, each hosting 256 antennas creating a total of 131,072 antennas. A first verification system towards SKA 1-Low, Aperture...
Software-Defined Radio (SDR) technology has already cleared up passive radar applications. Nevertheless, until now, no work has pointed how this flexible radio could fully and directly exploit pulsed radar signals. This paper aims at introducing this field of study presenting not only an SDR-based radar-detector but also how it could be conceived on a low power consumption device as a tablet, which...
Ultra-dense cellular networks are emerging as one key characteristic of 5G wireless networks. In this context, frequency reuse is a fundamental technology enabler for efficient utilization of limited spectrum resources. In this paper, we investigate the in-band Full-Duplex (FD) self-backhauling architecture, in which Base Stations (BSs) operate on the same spectrum used by the users to access the...
The Software PARIS Interferometric Receiver (SPIR) was conceived as a multiple beam-forming GNSS-Reflectometry receiver capable of implementing different signal processing strategies (clean-replica, interferometric, etc.) in order to demonstrate the synoptic capabilities for sea-surface altimetry using the interferometric GNSS-R technique. The instrument has been designed as a 16-channel very-high...
We developed a SFCW sparse array radar system for 3D imaging, which consists from 16 transmitters and 16 receivers and operates at the frequency range from 270MHz to 8GHz. The 2D antenna array layout was optimized using the middle point approximation. Several image reconstruction methods, which include the least square, Compressive Sampling Matching Pursuit and Regularized Orthogonal Matching Pursuit...
Degraded communication performance due to feedback delay is recognized in multiple-input multiple-output (MIMO) eigenbeam space-division multiplexing (E-SDM) in time-varying channels. The degree of performance degradation differs depending on the MIMO reception technique used. The degree of degradation in cases where spatial filtering techniques such as the zero-forcing (ZF) technique or the minimum...
To meet yet higher speed and capacity demands, 5G will turn to mm-waves for more bandwidth. In this paper some receiver design issues occurring when moving from current 4G bands to mm-wave frequencies are discussed. The local oscillator phase noise increases by 6dB/octave with frequency and will ultimately limit spectrum efficiency. To analyze this, a phase noise model, based on a test chip designed...
In this paper, pattern division multiple access with large-scale antenna array (LSA-PDMA) is proposed as a novel non-orthogonal multiple access (NOMA) scheme. In the proposed scheme, pattern is designed in both beam domain and power domain in a joint manner. At the transmitter, pattern mapping utilizes power allocation to improve the system sum rate and beam allocation to enhance the access connectivity...
In this paper, we address the orthogonal frequency division multiplexing (OFDM) downlink transmission in scenarios abundant of scatters when the high- speed rail (HSR), equipped with partly calibrated massive uniform linear array (ULA), is in high- speed motion relative to the base station. A high- resolution beamforming network is designed to separate multiple Doppler frequency offsets (DFOs) in...
Due to the enormous needs for signal processing and hardware constraints, the full digital implementation for a large antenna array at mmWave frequencies becomes intractable. Hence, receiver design for MIMO system with massive hybrid array is very demanding, particularly for subarray structure. In this paper, we propose two low- complexity uplink multiuser receiver design schemes (single-beam and...
In this study, a dual channel transmission concept over a single array with different frequencies and angle of arrivals without time division is presented. A time modulation scheme is applied to an ordinary linear array and the difference between main and fundamental radiation which can be steered independently with different frequencies is exploited in order to achieve a dual channel. By this way,...
This paper presents the results of the Software-defined Multiband Array Passive Radar (SMARP) project. The objective of the project was to design and realize a multiband passive radar demonstrator based on a software-defined solution and oriented to coastal surveillance applications. This work has been conceived in the framework of the Italian National Plan for Military Research. The project overall...
In next generation of mobile networks, the 5G, millimeter-wave communication is considered one of the key technologies. It allows high data rate as well as the utilization of large antennas for massive multiple-input-multiple-output (MIMO) and beamforming. However, it is mandatory that transmitter and receiver perform a training of their beams in order to gain all the benefits of a large array gain...
We propose a novel method to construct beam codebooks, i.e. a set of beamforming weights, for beam sweeping and data transmission in mmWave massive MIMO channels. The proposed beam codebooks are designed according to the statistical distribution of the channel's angles of departure in order to efficiently sweep the angular space covered by the beams. We first present a general closed-form construction...
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