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A high-speed full-duplex system based on IFoF for the RAN is proposed and experimentally demonstrated, whose wireless carrier operates at the 28GHz-frequency. A 28GHz-full-duplex BS module is developed and the complete uplink/downlink of the system is experimentally established, which supports up to 2GHz analog bandwidth, and meanwhile 1Gb/s BPSK signal accomplishes the uplink/downlink transmission...
Phase offset is inevitable in asynchronous physical-layer network coding (PNC) systems, which restricts the accuracy of PNC decoding. To address this issue, this paper proposes a half-blind equalization based on pre-distortion. In the scheme, the intentional phase distortion is pre-brought into the symbols of one user, and then, it is utilized by the relay to equalize the received signals and modify...
Power line communication is a widely used technology in the smart grid, which has the advantages of wide coverage area and no rewiring. However, the power line has hostile channel characteristics like strong noise, violent signal attenuation and time-varying, which lead to the unreliability of power line communication. Based on this, in this paper we present a new MAC protocol to improve the stability...
We introduce a model of a combination of particular low density parity check (LDPC) code and quadrature-quadrature phase shift keying (Q2PSK) constellation for the application of the downlink of the unmanned aerial vehicle (UAV) data chain. This model is a modification of the combination of LDPC code and constant envelope Q2PSK (CEQ2PSK) constellation. It achieves higher bandwidth efficiency of 4/3...
This paper introduces a time-hopping (TH) system for rapid on-off-division duplex (RODD), with this method, virtual full-duplex communication at the frame transmission level can be realized. However because of the randomness of the transmission timing, the slots may have a collision with a high probability. So it's very important to establish a model to calculate the collision ratio, and analyze the...
We presented a combination of a new coding technique called Multi Slot Amplitude Coding (MSAC). By jointing Optisystem and Matlab, the coding and decoding of MSAC, Duty Cycle Division Multiplexing (DCDM) and Absolute Polar Duty Cycle Division Multiplexing (APDCDM) all are achieved in a same Free Space Optical (FSO) communication system. By comparing average energy of each symbol, different mapping...
The paper presents an efficient parallel carrier synchronization algorithm suitable for high speed demodulator system and easy to implement on FPGA platform. The parallel algorithm combines the phase frequency detector (PFD) algorithm of the fast capture and the phase detector (PD) algorithm of the stable tracking. First, it can quickly capture carrier frequency offset by using PFD algorithm. Then,...
In a conventional wireless transmission system, studies are usually focus on increasing transmission rate instead of energy efficiency (EE). In this paper, we propose a hybrid transmission strategy to investigate the EE in a wireless transmission system. In this hybrid transmission strategy, the transmission mode is switched between the direct transmission (DT) mode and the amplify-and-forward relay...
Multi-dimensional wireless transmission system can effectively overcome shortcomings attach to a single-dimensional system such as low transmission efficiency, poor transmission stability. In present paper, a novel multidimensional receiving coil and its peripheral circuits are represented. Base on the circuits' models, compensation capacitances, output power and system efficiency are studied.
This work investigates the problem of channel sensing order in distributed cognitive networks with multiuser, in which the set of active secondary users is randomly changing in each time slot. We model this problem into a non-cooperative game and define a generalized interference metric. The optimization objective is to minimize the generalized interference metric. To cope with this problem, we propose...
In a two-way relaying (TWR) system, two nodes wish to exchange information with the help of relays. Previous work on TWR is mainly based on the assumption that the channel quality remains constant for one round of data exchange, however, the realistic channel fluctuates over time. In this paper, we study the outage behavior of a decode-and-forward (DF) TWR system over block fading channels where the...
Filter optimization of out-of-band emission plays an important role for FBMC-OQAM system. The main idea of this paper is to minimize the stopband energy with constraints of sidelobe and interchannel interference (ICI)/intersymbol interference (ISI) by optimizing the filter coefficients. The main contribution is that the improved approach reduces the stopband energy and suppresses the sidelobe simultaneously...
A novel transceiver of combining (n, n(n-1), n-1) permutation group code (PGC) with multiple frequency shift keying (MFSK) modulation was designed for high reliability against non-hostile man-made multiple frequency interferences and multipath fading on wireless channels. The combination of PGC and MFSK generates a new coded modulation scheme, named as time-frequency shift keying (TFSK), which can...
A partial parallel architecture for LDPC (Low Density Parity Check Code) decoder is proposed. The overall architecture is based on MIMD (Multiple Instruction Stream Multiple Data Stream), the internal calculation unit is based on SIMD (single instruction Stream multiple data Stream). The processor uses the programmable method to realize the NMS (normalized minimum sum) decoding algorithm, can get...
This paper simplifies the chase decoding algorithm for TPC codes for a particular modulation scheme (BPSK). Without reducing the decoding performance, the multiplication of the new algorithm is 33% of the original algorithm. The access algorithm of receiving matrix [R] is also optimized, and the access time of receiving matrix [R] is reduced to 3%. Finally, the 800M bps TPC decoder was implemented...
In harsh channel conditions, the quality of the synthetic speech at low bit rate would be affected severely. In order to improve the robustness of the vocoder and make it more resilient to errors in random channel, unequal error protection (UEP) channel coding is usually adopted. However, when the errors cannot be corrected in some cases, UEP channel coding will not improve the quality of the synthetic...
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