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TDD is one of the duplex technologies used by the mobile communication system, and its role is to separate the receiving and transmitting channel (the uplink or downlink). This paper presents a high speed TDD baseband data processing system realized on the FPGA. Through the data transceiver loop method, it's verified that the transceiver switching rate of the TDD mode can be 8KHZ and the data transfer...
This paper presents a wide-band receiver at 2.4GHz and 5GHz for 4×4 MIMO wireless communication system. This design is proposed and realized using super heterodyne architecture solution. Dual conversion structure is used in this receiver system. The receiver benefits from RF part, control part and phase shifter part. The carrier of this transceiver is 1.82GHz and 4.42GHz, and the local oscillation...
Co-Channel Dual Polarization (CCDP) technology is an efficient way to double the link capacity in modern communication system. However, the consequent polarization interferences become an inevitable problem to fight. Therefore, a Cross-Polarization Interference Canceller (XPIC) is necessary against the cross-talks. This paper focuses on the baseband XPIC technology and builds a simulink model to show...
Nowadays, the 24GHz band is allowed temporarily for car radars by European Telecommunication Standards Institute (ETSI) until 2013, when the hardware technology (MMICs, antennas, etc.) will be mature enough to enable the development and production of automotive radar modules at the 76–81 GHz band. In this paper, a common structure of homodyne LFMCW (Liner Frequency Modulated Continuous Wave) radar...
A new multi-core-based tree routing protocol for HIP-multicast model is proposed, which includes the process of data transmission, message format, structure of routing table and dynamically update algorithm. The theoretical analysis and simulation results show that the new protocol is suitable for HIP-multicast model, and has low complexity, good scalability and high efficiency.
This paper gives a brief overview of voltage controlled oscillator(VCO) based on Si CMOS and SiGeBiCMOS process technologies. The status of designing techniques for high performance VCO is summarized because of its importance for high-speed communication systems and radar sensors. Then, the development tendency of VCO is introduced.
Aimed at the problem of the near-field imaging in real time, a near-field narrow 2-D imaging algorithm based on the combination of single-input multiple output array (SIMO) and synthetic aperture radar (SAR) is proposed. By combining a real aperture and synthetic aperture, a 2-D synthetic aperture plane which is in terms of spatial sampling to obtain the target scattering information is synthesized...
This paper investigates the inverse matrix of near-space elevation multi-aperture synthetic aperture radar(SAR) wide-swath remote sensing. Note that near-space is defined as the altitude region between 20 and 100 km, which is much higher than air-borne height, and much lower than space-borne height. Besides, the flight speed of near-space aircraft is between air-borne aircraft and space-borne aircraft...
Waveguide T-junction and directional couplers are widely used in microwave/millimeter wave systems, because its circuit is simply and easily to be designed and fabricated. In this paper, a ka-band E-plane rectangular waveguide power divider is proposed and optimized. The first level of the network is the T-junction, which can halve the power for the first time, and the second level are two 3dB directional...
This paper proposes an improved 1 to 4 power divider based on oversized-coaxial and radial waveguide. To widen the bandwidth of the divider/combiner, an axially symmetric oversized coaxial waveguide is used to transform input to the radial waveguide, and at the bottom of the radial waveguide, stepped-impedance technology is used to realize the impedance match. According to EM simulations, the simulated...
In this paper, two classes of Ka-band Substrate Integrated Waveguide(SIW) power divider are presented and studied. The advantages of the SIW technique are its low profile, low-lost, mass-productive, ease of fabrication and fully integrated with planar circuits. All the modules are designed to be operated in a wide frequency range. The Y-junction shows a bandwidth of 29.4%.
This paper proposes a novel approximation for the round-trip distance of the near-field echoed data based on a planar 2-D synthetic aperture planar array. A near-field narrow imaging algorithm based on the novel approximation is proposed. Comparisons of the proposed approximation and the Fresnel approximation are also demonstrated. The errors of the proposed approximation are negligible when the antenna...
In this paper, an ultra-low-power baseband processor for a UHF Passive RFID Tag is presented. It proposes a prominent RFID tag baseband architecture which is compliant with the ISO18000-6B UHF RFID protocol. Several low-power design approaches are employed to reduce the power consumption, including low voltage low operation frequency approach, clock gating technique, clock strobe design, asynchronous...
Web database security is a very important issue in e-commerce. This paper presents a new Web database security model. It utilizes the host identity protocol (HIP), which is being defined by the IETF, and a proposed user identity exchange, to achieve authentication of host identity and user identity, and combines it with the database system itself and encryption to guarantee Web database security and...
Millimeter-wave radar has attracted much attention as a replacement of some infrared or laser systems currently in use. In this paper, an approach of developing high performance waveform for full-coherent millimeter-wave radar is proposed. With good frequency configuration and optimal utilization of DDS (direct digital synthesizer), PLL (phase locked loop) and FPGA (field programming gate array),...
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