Ammonia-rich substrates inhibit the anaerobic digestion (AD) process and constitute main reason for low energy recovery in full-scale reactors. It is estimated that many AD reactors are operating ammonia induced "inhibited steady-state" with significant losses of potential biogas production yield. To date there not any reliable methods to alleviate toxicity effect or efficiently digest ammonia-rich waste. In current study, bioaugmentation as a possible method mesophilic continuously...

Recently, single carrier block transmission (SCBT) has received much attention in high-rate phase-coherent underwater acoustic communication. However, minimum-mean-square-error (MMSE) linear FDE may suffer performance loss the severely time dispersive channel. To combat channel distortion, a novel multi-channel receiver with maximum ratio combining and low complex T/4 fractional iterative frequency domain equalization (FDE) is investigated to improve diversity gain bit error rate (BER)...

Single-carrier with frequency domain equalization (SC-FDE) has been considered for bandwidth efficiency underwater acoustic (UWA) communication recently due to its reduced computational complexity and low peak-to-average power ratio. A multi-channel time-frequency method pseudurandom noise (PN) based SC-FDE is proposed in this paper. The equalizer includes a followed by order adaptive time decision feedback (DFE). algorithm applied the real data receiving from lake test conducted November...

Orthogonal time-frequency-space (OTFS) modulation has shown significant error performance advantages over orthogonal frequency division multiplexing (OFDM) in time-varying channels. However, the symbols OTFS frames still suffer from inter-Doppler interference (IDI) and inter-symbol (ISI). In this letter, we propose a two dimensional (2D) adaptive multichannel decision feedback equalizer (DFE) to combat interference. The proposed receiver constructs input signal of DFE based on characteristic...

Single-carrier frequency-domain equalization (SC-FDE) is a promising technique for coherent high-rate underwater acoustic (UWA) communications. In this paper, time-frequency domain turbo (TFD-TE) scheme proposed single-carrier modulation. The TFD-TE to couple multi-channel frequency equalizer with phase rotation compensation and low-order single-channel time-domain equalizer. To mitigate the error propagation further enhance receiver performance, bidirectional that combined soft outputs of...

This work proposes a novel interleave-division multiple access (IDMA) system based on cyclic shift keying (CSK) modulation, named CSK-IDMA, for multiuser underwater acoustic (UWA) communications. The CSK modulation uses circular of the spreading sequence to represent information, which can be viewed as special M-ary spread spectrum modulation. Compared with conventional direct-sequence (DSSS) technique, overcomes gain versus data rate limitations. proposed scheme adopts IDMA technique reduce...

Collaborative control methods employed in swarm robotic systems often deal with bulks of information from the local interactions among agents and between environment. The efficiency overall integration decentralized distributed can show major impacts on collective behaviour swarm. It is crucial to establish an approach that bridges existing gap present realistic system real-world enforcements. Therefore, this review paper vividly captures challenges faced mechanisms within systems, how...

—The propagation prediction research has mainly focused on studying the radio models in urban or rural land areas. In this paper, we extend a method for 950 MHz over sea based ITU-R Recommendation P.1546-5. A gauge of accuracy Free Space model, correction Okumura-Hata model and P.1546-5 is presented. The evaluated using measurement results which were obtained by utilizing pilot signal commercial GSM network around Haikou, China. comparison enabled hit rate metrics. Measurement show that...

Phase-coherent underwater acoustic (UWA) communication systems typically employ multiple hydrophones in the receiver to achieve spatial diversity gain. However, small platforms can only carry a single transducer which not provide In this paper, we propose single-carrier with frequency domain equalization (SC-FDE) for phase-coherent synthetic aperture communications virtual array is generated by relative motion between transmitter and receiver. This paper presents results using SC-FDE through...

Underwater acoustic (UWA) channels exhibit double selectivity in both time and frequency domains, posing significant challenges to reliable UWA communications. This correspondence paper presents a novel spatial block coding scheme integrated with complementary code keying (CCK) modulation exploit diversity against doubly selective fading channels. The proposed spatial-CCK utilizes multiple transmit transducers extends the traditional CCK set improve receiver performance. We introduce design...

The Hyperloop system is a novel conceptual aimed to provide high speed public transportation service in the future, featured with reduced-pressure tube which pressurized capsules ride on cushion of air that driven by combination linear induction motors and compressors.The project developing based crowdfunding-sourcing mode, dramatically different traditional way.Identifying hazard would be helpful publics' acceptance safety from concept stage.If all hazards were dealt properly, could more...

This letter presents a novel design of high rate complementary code keying (CCK) modulation scheme (named QAM-CCK) that is suitable for bandwidth efficient wireless link adaptation. The proposed QAM-CCK can increase the efficiency CCK signaling by simultaneously implementing quadrant and phase modulations. We introduce an optimal criterion based on weighted minimum Euclidean distance to optimize mapping with average bit error probability. In order utilize inherent coding gain QAM-CCK, we...

The performance of frequency-domain equalization in a SC-FDE system is affected by the precision channel estimation results and methods based on compressive sensing have better sparse condition such as underwater acoustic communication channels. However, commonly used greedy algorithm requires sparsity to terminate recursive process. Unlike many existing which treated known factor, we propose method with predetermined wavelet decomposition. Typical LS applied first decomposition estimated...

In this letter, we present a novel spatial modulation (SM) transmission with multiple antennas by applying non-orthogonal complementary code keying (CCK). We propose high-performance turbo receiver for CCK-SM signaling over frequency-selective fading channels. Compared conventional SM, our proposed transceiver utilizes the advantages of CCK to achieve substantial coding gain without cost high complexity. Our incorporates iterative block decision feedback equalization soft decoder clear...

Microwave switches are widely used to control the on-off or conversion of microwave signal transmission paths. In this paper, a SPDT (Single-Pole-Double-Throw) switch based on X-band is designed, whose main function input two channels through switch. The built-in limiter and low-noise amplifiers provide certain channel gain for system link, realize outputs with different channels.

Abstract Modern radars use complex waveforms to obtain high detection performance and low probabilities of interception identification. Signals intercepted from multiple overlap considerably in both the time frequency domains are difficult separate with primary parameters. Time–frequency analysis (TFA), as a key signal-processing tool, can provide better insight into signal than conventional methods. In particular, among various types TFA, parameterized time-frequency (PTFA) has shown great...

Digital twin technology is promising, and has great advantage for traffic management to study, predict, simulate experiment, from driving physical innovation virtual testing. The goal remains the same: improve safety, regulate flow, ease urban congestion. At present, a mature digital transportation model not been established at social level. In this paper, method proposed construct by extracting environmental features entities such as roads, lights, vehicles, combining optimization algorithm...