Successive-relaying-aided decode-and-forward coherent versus noncoherent cooperative multicarrier space–time shift keying

Abstract—Successive-relaying-aided (SR) cooperative multi-carrier (MC) space–time shift keying (STSK) is proposed for frequency-selective channels. We invoke SR to mitigate the typical 50% throughput loss of conventional half-duplex relaying schemes and MC code-division multiple access (MC-CDMA) to circumvent the dispersive effects of wireless channels and to reduce the SR-induced interference. The distributed relay terminals form two virtual antenna arrays (VAAs), and the source node (SN) successively transmits frequency-domain (FD) spread signals to one of the VAAs, in addition to directly transmitting to the destination node (DN). The constituent relay nodes (RNs) of each VAA activate cyclic-redundancy-checking-based (CRC) selective decode-and-forward (DF) relaying. The DN can jointly detect the signals received via the SN-to-DN and VAA-to-DN links using a low-complexity single-stream-based joint maximum-likelihood (ML) detector. We also propose a differentially encoded cooperative MC-CDMA STSK scheme to facilitate communications over hostile dispersive channels without requiring channel estimation (CE). Dispensing with CE is important since the relays cannot be expected to altruistically estimate the SN-to-RN links for simply supporting the source. Furthermore, we propose soft-decision-aided serially concatenated recursive systematic convolutional (RSC) and unity-rate-coded (URC) cooperative MC STSK and investigate its performance in both coherent and noncoherent scenarios

Successive-relaying-aided decode-and-forward coherent versus noncoherent cooperative multicarrier space–time shift keying

Abstract—Successive-relaying-aided (SR) cooperative multi-carrier (MC) space–time shift keying (STSK) is proposed for frequency-selective channels. We invoke SR to mitigate the typical 50% throughput loss of conventional half-duplex relaying schemes and MC code-division multiple access (MC-CDMA) to circumvent the dispersive effects of wireless channels and to reduce the SR-induced interference. The distributed relay terminals form two virtual antenna arrays (VAAs), and the source node (SN) successively transmits frequency-domain (FD) spread signals to one of the VAAs, in addition to directly transmitting to the destination node (DN). The constituent relay nodes (RNs) of each VAA activate cyclic-redundancy-checking-based (CRC) selective decode-and-forward (DF) relaying. The DN can jointly detect the signals received via the SN-to-DN and VAA-to-DN links using a low-complexity single-stream-based joint maximum-likelihood (ML) detector. We also propose a differentially encoded cooperative MC-CDMA STSK scheme to facilitate communications over hostile dispersive channels without requiring channel estimation (CE). Dispensing with CE is important since the relays cannot be expected to altruistically estimate the SN-to-RN links for simply supporting the source. Furthermore, we propose soft-decision-aided serially concatenated recursive systematic convolutional (RSC) and unity-rate-coded (URC) cooperative MC STSK and investigate its performance in both coherent and noncoherent scenarios

MC-CDMA aided multi-user space-time shift keying in wideband channels

In this paper, we propose multi-carrier code division multiple access (MC-CDMA)-aided space-time shift keying (STSK) for mitigating the performance erosion of the classic STSK scheme in dispersive channels, while supporting multiple users. The codewords generated by the STSK scheme are appropriately spread in frequency-domain (FD) and transmitted over a number of parallel frequency-?at subchannels. We propose a new receiver architecture amalgamating the single-stream maximum-likelihood (ML) detector of the STSK system and the multiuser detector (MUD) of the MC-CDMA system. The performance of the proposed scheme is evaluated for transmission over frequency-selective channels in both uncoded and channel-coded scenarios. The results of our simulations demonstrate that the proposed scheme overcomes the channel impairments imposed by wideband channels and exhibits near-capacity performance in a channel-coded scenario

DESIGN SUBSEA POWER GENERATION SYSTEM

Subsea technologies are now moving further where the operation now done by using latest subsea equipment that are more efficient and cost effective. The main issue is that these equipment powered by the power supplied from the platform which causes the power losses due to the cable distance and friction inside the cable. The main objective of this study is to design subsea power generation system that can overcome the stated issue in order to reduce the cable length that lead to power losses. In order to conduct this research, a structured mechanical systems design was adopted. The concept generation for an alternative power generation was made by using the morphological chart. Subsequently, concept selection was done by using the weighted score matrix. Then, in the assembly drawing, the system configuration shows how the part are related and connected to other parts of the assembly. Mathematical modeling was produced using the governing equation gathered from the literature. Using the data from the mathematical modeling, the detail design was produced using the AUTOCAD and CATIA softwares. The deliverables of the project are assembly drawing and the design specification needed to operate a Remote Operated Vehicle (ROV)

OFDMA/SC-FDMA aided space-time shift keying for dispersive multi-user scenarios

Motivated by the recent concept of Space-Time Shift Keying (STSK) developed for achieving a flexible diversity versus multiplexing gain trade-off, we propose a novel Orthogonal Frequency Division Multiple Access (OFDMA)/Single Carrier Frequency Division Multiple Access (SC-FDMA) aided multi-user STSK scheme for frequency-selective channels. The proposed OFDMA/SC-FDMA STSK scheme is capable of providing an improved performance in dispersive channels, while supporting multiple users in a multiple antenna aided wireless system. Furthermore, the scheme has the inherent potential of benefitting from the low-complexity single-stream Maximum-likelihood (ML) detector. Both an uncoded and a sophisticated near-capacity coded OFDMA/SC-FDMA STSK scheme were studied and their performances were compared in multiuser wideband Multiple-Input Multiple-Output (MIMO) scenarios. Explicitly, OFDMA/SC-FDMA aided STSK exhibits an excellent performance even in the presence of channel impairments due to the frequency-selectivity of wideband channels and proves to be a beneficial choice for high capacity multi-user MIMO systems

Sejarah Bahasa Melayu Sebagai Bahasa Matematik

Di sini, kami mengumpulkan segala maklumat penting tentang kewujudan angka Melayu semenjak kurun ke3/ 4 Masihi. Maklumat dikumpulkan daripada prasasti-prasasti Melayu dan manuskrip-manuskrip Melayu dan Eropah

Mental illness action taken in workplace

It is approximately 450 million people have been analysed with mental illness around the world, where mental illness, substance abuse and neurological diseases contribute to 13% of the worldwide disease burden. The World Health Organization (WHO) gauge that 1 in 4 individuals experience mental illness at a few points in their life. That means almost 25% of the population has a mental illness. According to Datuk Seri Dr. S. Subramaniam Depression, on normal, accounts for 4.3% of the by and large burden of cobalt disease, which is one of the biggest causes of morbidity. Mental illness or also been called as mental health disorders, it is a wide scope of emotional well-being problem of scatters that impact your personality, considering and conduct. Tension issue, dietary issues, addictive practices, discouragement and schizophrenia which are the instances of dysfunctional behaviour

PENGEMBANGAN USAHA KECIL MENENGAH PENGRAJIN PISAU DAPUR DI DESA MONCONGLOE LAPPARA KABUPATEN MAROS SULAWESI SELATAN MELALUI PROGRAM PKM

PENGEMBANGAN USAHA KECIL MENENGAH PENGRAJIN PISAU DAPUR DI DESA MONCONGLOE LAPPARA KABUPATEN MAROS SULAWESI SELATAN MELALUI PROGRAM PK

Histological study of the interaction between Exserohilum Longirostratum, barnyard grass, and rice var. MR219

The course of infection and the development of Exserohilum longirostratum (Subramanian) Sivanesan on barnyardgrass (Echinochloa crus-galli (L.) Beauv. spp. crusgalli) and rice (Oryza sativa L. var. MR219) were studied under light microscopy (LM) and scanning electron microscopy (SEM). Observation under SEM indicated similarity of the gross anatomy of both rice and barnyard grass leaves. Meanwhile, germination of the conidium of E. longirostratun was found to be not influenced by inoculation time as the conidia started to germinate 4 hours after the inoculation on both leaf surfaces. However, the patterns and number of germ tubes and appressoria formation were influenced by host plants. On barnyard grass, the primary infection process consisted of the conidial germination, elongation of the germ tube, formation of the appresorial initials, maturation of the appressoria, and formation of secondary hyphae. Successful penetration was followed by an extensive colonization of the invaded epidermal cell wall. Observation of the cross section revealed that the infection hyphae expanded into a spherical vessel and colonized the cells, causing the collapse of the epidermal cells and resulting in the formation of necrotic lesions of infected and adjacent tissue. Although fungus successfully grew and produced germtube on rice, both the primary infection process and the successful penetration of the cuticle were not observed on rice. The conidia germinated and produced slender and thin germ tube, with occasional appressorium formation. Germ tubes and appressoria formation on the barnyard grass (70% and 92%, respectively) were significantly higher as compared to rice leaves (51% and 10%). It was observed that the mycelium infected barnyard grass much faster (less than 24 h) than the conidia as it immediately formed appressorium without having the need, like the conidia, to germinate first. These results suggest that it may be possible to utilize E. longirostratum as a bioherbicide to control barnyard grass under rice production in Malaysia