Pub Date : 2022-05-24DOI: 10.1109/NCC55593.2022.9806770
Moakala Tzudir, Shikha Baghel, Priyankoo Sarmah, S. Prasanna
Ao is a language spoken in Nagaland in the North-East of India. It is a low-resource tone language under the Tibeto-Burman language family. It consists of three tones, namely, high, mid and low. It has three distinct dialects of the language viz. Chungli, Mongsen and Changki. This paper presents an automatic dialect identification in Ao using the excitation source feature. The objective of a dialect identification system is to identify a speech variety within a language. The goal of this study is to determine if the excitation source features such as Residual Mel Frequency Cepstral Coefficient (RMFCC) can be exploited to discriminate the three dialects in Ao automatically. In addition, vocal tract system features, namely Mel Frequency Cepstral Coefficients (MFCC) and Shifted Delta Cepstral (SDC) coefficients, are used as the baseline methods. The RMFCC features are obtained from the Linear Prediction (LP) residual signal, while MFCC features are derived from the smooth spectrum of the speech signal. SDC coefficients are explored to provide additional temporal information. This work is evaluated on trisyllabic words uttered by 36 speakers for the three dialects of Ao. A Gaussian Mixture Model (GMM) based classifier is used for classification. The performance of the system yields a better dialect identification accuracy rate when all three features are combined.
{"title":"Analyzing RMFCC Feature for Dialect Identification in Ao, an Under-Resourced Language","authors":"Moakala Tzudir, Shikha Baghel, Priyankoo Sarmah, S. Prasanna","doi":"10.1109/NCC55593.2022.9806770","DOIUrl":"https://doi.org/10.1109/NCC55593.2022.9806770","url":null,"abstract":"Ao is a language spoken in Nagaland in the North-East of India. It is a low-resource tone language under the Tibeto-Burman language family. It consists of three tones, namely, high, mid and low. It has three distinct dialects of the language viz. Chungli, Mongsen and Changki. This paper presents an automatic dialect identification in Ao using the excitation source feature. The objective of a dialect identification system is to identify a speech variety within a language. The goal of this study is to determine if the excitation source features such as Residual Mel Frequency Cepstral Coefficient (RMFCC) can be exploited to discriminate the three dialects in Ao automatically. In addition, vocal tract system features, namely Mel Frequency Cepstral Coefficients (MFCC) and Shifted Delta Cepstral (SDC) coefficients, are used as the baseline methods. The RMFCC features are obtained from the Linear Prediction (LP) residual signal, while MFCC features are derived from the smooth spectrum of the speech signal. SDC coefficients are explored to provide additional temporal information. This work is evaluated on trisyllabic words uttered by 36 speakers for the three dialects of Ao. A Gaussian Mixture Model (GMM) based classifier is used for classification. The performance of the system yields a better dialect identification accuracy rate when all three features are combined.","PeriodicalId":403870,"journal":{"name":"2022 National Conference on Communications (NCC)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123728530","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-05-24DOI: 10.1109/NCC55593.2022.9806805
Abhijeet C. Gaonkar, Deven G. Patanvariya, Pragati Patel
A multi-band rectangular dielectric resonator an-tenna (RDRA) is proposed in this study for WiMAX, Wireless Local Area Network (WLAN) applications. The proposed geometry is based on combination of golden ratio and koch snowflake fractal approach. The proposed DRA geometry has been designed using low-cost alumina dielectric material. The DRA is fed by a trapezoidal a conformal strip feed. The proposed triple-band antenna operates at 2.5/3.8/4.9 GHz. The designed triple-band antenna with extremely low-cost and low-profile is very suitable for multi-band mobile communication systems. The presented dielectric resonator antenna (DRA) is having stable radiation patterns (nearly directional pattern) for each operating band. Additionally, the RDRA achieves an over-all total efficiency of more than 90% at the desired frequency bands. The proposed antenna is suitable for different wireless applications such as WLAN (5.2 GHz), WiMAX (2.6/3.5 GHz).
{"title":"Fractal based Rectangular DRA for Multi-band Applications","authors":"Abhijeet C. Gaonkar, Deven G. Patanvariya, Pragati Patel","doi":"10.1109/NCC55593.2022.9806805","DOIUrl":"https://doi.org/10.1109/NCC55593.2022.9806805","url":null,"abstract":"A multi-band rectangular dielectric resonator an-tenna (RDRA) is proposed in this study for WiMAX, Wireless Local Area Network (WLAN) applications. The proposed geometry is based on combination of golden ratio and koch snowflake fractal approach. The proposed DRA geometry has been designed using low-cost alumina dielectric material. The DRA is fed by a trapezoidal a conformal strip feed. The proposed triple-band antenna operates at 2.5/3.8/4.9 GHz. The designed triple-band antenna with extremely low-cost and low-profile is very suitable for multi-band mobile communication systems. The presented dielectric resonator antenna (DRA) is having stable radiation patterns (nearly directional pattern) for each operating band. Additionally, the RDRA achieves an over-all total efficiency of more than 90% at the desired frequency bands. The proposed antenna is suitable for different wireless applications such as WLAN (5.2 GHz), WiMAX (2.6/3.5 GHz).","PeriodicalId":403870,"journal":{"name":"2022 National Conference on Communications (NCC)","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115320607","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-05-24DOI: 10.1109/NCC55593.2022.9806744
Sarthak Joshi, Rishabh Roy, R. Bhat, Preyas Hathi, N. Akhtar
The IEEE 802.11ax standard (Wi-Fi 6), among other features, adopts a feature called spatial reuse, where new transmissions can be carried out in presence of ongoing, interfering transmissions from nodes in an overlapping basic service set (OBSS). Specifically, a node can adjust its threshold for detecting the interference, by setting a parameter called OBSS Power-Detect level $(text{OBSS}_{-}text{PD}_{text{level}})$. When a node hears an ongoing transmission from an OBSS node, if its received signal strength indicator (RSSI) is below the $text{OBSS}_{-}text{PD}_{text{level}}$, the node is said to have a spatial reuse opportunity. The node can transmit at a limited transmit power (TX_PWR) during the spatial reuse opportunity. The feasible values of $text{OBSS}_{-}text{PD}_{text{level}}$ and TX_PWR must satisfy certain constraints laid out by the IEEE 802.11ax standard. In this work, we propose an algorithm that first obtains $text{OBSS}_{-}text{PD}_{text{level}}$ thresholds for maximizing the number of spatial reuse opportunities, and then selects the one that minimizes the packet error rate among these $text{OBSS}_{-}text{PD}_{text{level}}$ thresholds. The trade-off involved is the following: setting $text{OBSS}_{-}text{PD}_{text{level}}$ to a high value increases the number of spatial reuse opportunities, but necessitates transmissions to be at lower transmit power (due to the constraint specified by the standard) resulting in higher packet error rates, and vice versa. The proposed algorithm dynamically varies $text{OBSS}_{-}text{PD}_{text{level}}$ based on packet error rates. Via simulations, we show that the proposed dynamic algorithm performs better (in terms of achieving a higher throughput and a lower packet error rate) than a naive method which adopts a constant $text{OBSS}_{-}text{PD}_{text{level}}$ threshold and the case when the spatial reuse is not adopted. When the spatial reuse is implemented using the proposed algorithm, we also explore the performance of different traffic models served using QoS queues having different priorities and transmission parameters.
{"title":"Dynamic Distributed Threshold Control for Spatial Reuse in IEEE 802.11ax","authors":"Sarthak Joshi, Rishabh Roy, R. Bhat, Preyas Hathi, N. Akhtar","doi":"10.1109/NCC55593.2022.9806744","DOIUrl":"https://doi.org/10.1109/NCC55593.2022.9806744","url":null,"abstract":"The IEEE 802.11ax standard (Wi-Fi 6), among other features, adopts a feature called spatial reuse, where new transmissions can be carried out in presence of ongoing, interfering transmissions from nodes in an overlapping basic service set (OBSS). Specifically, a node can adjust its threshold for detecting the interference, by setting a parameter called OBSS Power-Detect level $(text{OBSS}_{-}text{PD}_{text{level}})$. When a node hears an ongoing transmission from an OBSS node, if its received signal strength indicator (RSSI) is below the $text{OBSS}_{-}text{PD}_{text{level}}$, the node is said to have a spatial reuse opportunity. The node can transmit at a limited transmit power (TX_PWR) during the spatial reuse opportunity. The feasible values of $text{OBSS}_{-}text{PD}_{text{level}}$ and TX_PWR must satisfy certain constraints laid out by the IEEE 802.11ax standard. In this work, we propose an algorithm that first obtains $text{OBSS}_{-}text{PD}_{text{level}}$ thresholds for maximizing the number of spatial reuse opportunities, and then selects the one that minimizes the packet error rate among these $text{OBSS}_{-}text{PD}_{text{level}}$ thresholds. The trade-off involved is the following: setting $text{OBSS}_{-}text{PD}_{text{level}}$ to a high value increases the number of spatial reuse opportunities, but necessitates transmissions to be at lower transmit power (due to the constraint specified by the standard) resulting in higher packet error rates, and vice versa. The proposed algorithm dynamically varies $text{OBSS}_{-}text{PD}_{text{level}}$ based on packet error rates. Via simulations, we show that the proposed dynamic algorithm performs better (in terms of achieving a higher throughput and a lower packet error rate) than a naive method which adopts a constant $text{OBSS}_{-}text{PD}_{text{level}}$ threshold and the case when the spatial reuse is not adopted. When the spatial reuse is implemented using the proposed algorithm, we also explore the performance of different traffic models served using QoS queues having different priorities and transmission parameters.","PeriodicalId":403870,"journal":{"name":"2022 National Conference on Communications (NCC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127656246","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-05-24DOI: 10.1109/NCC55593.2022.9806780
Natarajan Lakshmi Prasad, Prasad Krishnan
We identify a large family of abelian codes that achieve the capacity of the binary erasure channel (BEC) under bit-MAP decoding. The codes in this family have rich automorphism groups, their lengths are odd integers, and they can asymptotically (in the block length) achieve any code rate. This family contains codes of prime power block lengths that were originally identified by Berman (1967) and later inves-tigated by Blackmore and Norton (2001), and also contains their generalization to any odd block length. We use Rajan and Siddiqi's (1992) characterization of abelian codes using discrete Fourier transform (DFT) to identify our code family and study their automorphism groups. We then use a result of Kumar, Calderbank and Pfister (2016) that relates the automorphism group of a code to its performance in the BEC to show that this code family achieves BEC capacity. The full version of this paper including the proofs of all claims and simulation results is available online [1]
{"title":"A Family of Capacity-Achieving Abelian Codes for the Binary Erasure Channel","authors":"Natarajan Lakshmi Prasad, Prasad Krishnan","doi":"10.1109/NCC55593.2022.9806780","DOIUrl":"https://doi.org/10.1109/NCC55593.2022.9806780","url":null,"abstract":"We identify a large family of abelian codes that achieve the capacity of the binary erasure channel (BEC) under bit-MAP decoding. The codes in this family have rich automorphism groups, their lengths are odd integers, and they can asymptotically (in the block length) achieve any code rate. This family contains codes of prime power block lengths that were originally identified by Berman (1967) and later inves-tigated by Blackmore and Norton (2001), and also contains their generalization to any odd block length. We use Rajan and Siddiqi's (1992) characterization of abelian codes using discrete Fourier transform (DFT) to identify our code family and study their automorphism groups. We then use a result of Kumar, Calderbank and Pfister (2016) that relates the automorphism group of a code to its performance in the BEC to show that this code family achieves BEC capacity. The full version of this paper including the proofs of all claims and simulation results is available online [1]","PeriodicalId":403870,"journal":{"name":"2022 National Conference on Communications (NCC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115766730","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-05-24DOI: 10.1109/NCC55593.2022.9806814
Ambati Dinesh, R. Swaminathan
Channel coding improves the error performance of digital communication systems. Blind parameter estimation of channel codes plays an important role in military communication systems. Further, it also provides some additional advantages in adaptive modulation and coding (AMC)-based systems, re- configurable receiver systems, etc. In this paper, we propose blind estimation algorithms to estimate the codeword length, code dimension, and generator polynomial of Bose-Chaudhuri- Hocquenghem (BCH) codes at the receiver over erroneous channel conditions assuming a non-cooperative scenario. The simulations are carried out on many test cases to validate the proposed blind estimation algorithms and the results are given to testify the algorithms. We infer that the probability of correct estimation of parameters increases with decrease in codeword length. Finally, it is also inferred that the proposed algorithm performs better than the existing algorithms reported in the literature.
{"title":"Blind Reconstruction of BCH Encoder over Erroneous Channel Conditions","authors":"Ambati Dinesh, R. Swaminathan","doi":"10.1109/NCC55593.2022.9806814","DOIUrl":"https://doi.org/10.1109/NCC55593.2022.9806814","url":null,"abstract":"Channel coding improves the error performance of digital communication systems. Blind parameter estimation of channel codes plays an important role in military communication systems. Further, it also provides some additional advantages in adaptive modulation and coding (AMC)-based systems, re- configurable receiver systems, etc. In this paper, we propose blind estimation algorithms to estimate the codeword length, code dimension, and generator polynomial of Bose-Chaudhuri- Hocquenghem (BCH) codes at the receiver over erroneous channel conditions assuming a non-cooperative scenario. The simulations are carried out on many test cases to validate the proposed blind estimation algorithms and the results are given to testify the algorithms. We infer that the probability of correct estimation of parameters increases with decrease in codeword length. Finally, it is also inferred that the proposed algorithm performs better than the existing algorithms reported in the literature.","PeriodicalId":403870,"journal":{"name":"2022 National Conference on Communications (NCC)","volume":"70 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125413641","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-05-24DOI: 10.1109/NCC55593.2022.9806776
Nadeem Atif, H. Balaji, Saquib Mazhar, S. R. Ahamad, M. Bhuyan
In the field of computer vision and scene under-standing, semantic segmentation is considered to be one of the most challenging task. This is due to the fact that it has to solve all the three standard vision problems, multi-class classification, object detection and image segmentation. One of the most promising areas of application of semantic segmentation is autonomous driving. The advent of deep-learning and the availability of large-scale datasets has enabled the research com-munity to reach to unprecedented performance heights compared to traditional machine learning algorithms. However, despite all the progress, existing learning methods still face the problem of class-imbalance because of which large classes get more attention and consequently the network becomes biased towards them. The problem of class-imbalance is particularly more prominent in urban road-scene datasets. This is because the layout of the scene captured by the camera mounted on a fixed location, naturally causes certain less important classes to occupy more area in the dataset. Trees, sky and buildings are some of the examples of large classes which frequently occur and occupy large areas despite the fact that they are less important with regards to driving related decision making. To tackle this problem, in this work, we have done the statistical analysis of the famous Cityscapes dataset to uncover the hidden patterns that large and small classes follow. Based on these patterns, we propose a semantic masking technique, that enables our proposed network MaskNet to pay more attention to regions where the smaller classes are more likely to occur. In this way, we see a significant performance increase with regards to smaller classes and the problem of class-imbalance is mitigated to a good extent.
{"title":"Semantic Masking: A Novel Technique to Mitigate the Class-Imbalance Problem in Real-Time Semantic Segmentation","authors":"Nadeem Atif, H. Balaji, Saquib Mazhar, S. R. Ahamad, M. Bhuyan","doi":"10.1109/NCC55593.2022.9806776","DOIUrl":"https://doi.org/10.1109/NCC55593.2022.9806776","url":null,"abstract":"In the field of computer vision and scene under-standing, semantic segmentation is considered to be one of the most challenging task. This is due to the fact that it has to solve all the three standard vision problems, multi-class classification, object detection and image segmentation. One of the most promising areas of application of semantic segmentation is autonomous driving. The advent of deep-learning and the availability of large-scale datasets has enabled the research com-munity to reach to unprecedented performance heights compared to traditional machine learning algorithms. However, despite all the progress, existing learning methods still face the problem of class-imbalance because of which large classes get more attention and consequently the network becomes biased towards them. The problem of class-imbalance is particularly more prominent in urban road-scene datasets. This is because the layout of the scene captured by the camera mounted on a fixed location, naturally causes certain less important classes to occupy more area in the dataset. Trees, sky and buildings are some of the examples of large classes which frequently occur and occupy large areas despite the fact that they are less important with regards to driving related decision making. To tackle this problem, in this work, we have done the statistical analysis of the famous Cityscapes dataset to uncover the hidden patterns that large and small classes follow. Based on these patterns, we propose a semantic masking technique, that enables our proposed network MaskNet to pay more attention to regions where the smaller classes are more likely to occur. In this way, we see a significant performance increase with regards to smaller classes and the problem of class-imbalance is mitigated to a good extent.","PeriodicalId":403870,"journal":{"name":"2022 National Conference on Communications (NCC)","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131732829","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-05-24DOI: 10.1109/NCC55593.2022.9806475
Pragati Patel, Abhijeet C. Gaonkar, M. Ayyappan
In this paper a novel wideband bow tie shaped Hemispherical Dielectric Resonator Antenna (HDRA) is pre-sented. The simulated results confirms a wide bandwidth of 2.29 GHz (2.69 - 4.98 GHz) ($S_{11}$ ≤ -10 dB is 61 % at 3.7 GHz) with an average gain of 5.5 dBi in the operating frequency band. Here, HDRA is kept complementary to each other to get bow tie shape. It ensures uniform excitation of the mode fields in each DRA element which leads to improvement in bandwidth. The mode investigated is T E111 mode at the first resonant frequency of 3.9 GHz. The effect of increasing the probe length on the resonance and radiation pattern is also investigated. The radiation patterns of antenna are directive in nature and radiation efficiency is more than 95 % in the entire band. The presented antenna is suitable for C band, most of L band and WiMAX applications.
{"title":"Novel Wideband Bow Tie shaped Hemispherical Dielectric Resonator Antenna","authors":"Pragati Patel, Abhijeet C. Gaonkar, M. Ayyappan","doi":"10.1109/NCC55593.2022.9806475","DOIUrl":"https://doi.org/10.1109/NCC55593.2022.9806475","url":null,"abstract":"In this paper a novel wideband bow tie shaped Hemispherical Dielectric Resonator Antenna (HDRA) is pre-sented. The simulated results confirms a wide bandwidth of 2.29 GHz (2.69 - 4.98 GHz) ($S_{11}$ ≤ -10 dB is 61 % at 3.7 GHz) with an average gain of 5.5 dBi in the operating frequency band. Here, HDRA is kept complementary to each other to get bow tie shape. It ensures uniform excitation of the mode fields in each DRA element which leads to improvement in bandwidth. The mode investigated is T E111 mode at the first resonant frequency of 3.9 GHz. The effect of increasing the probe length on the resonance and radiation pattern is also investigated. The radiation patterns of antenna are directive in nature and radiation efficiency is more than 95 % in the entire band. The presented antenna is suitable for C band, most of L band and WiMAX applications.","PeriodicalId":403870,"journal":{"name":"2022 National Conference on Communications (NCC)","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132590302","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-05-24DOI: 10.1109/NCC55593.2022.9806813
Chaitanya Chhichhia, Aakarshak Nandwani, Rachna Sharma, Y. Trivedi
In this paper, we consider a vertical Underwater Wireless Visible Light Communication (UWVLC) system, where the source is located at the surface of the sea. The distance between both the source and the destination is divided in certain intervals or layers. We assume turbulence in the underwater channel and the intensity of the turbulence, referred in term of scintillation index, varies between consecutive layers. Further, the turbulence based fading channel is modelled by log-normal distribution and the statistics of the channel vary from one layer to another. Thus, we assume cascaded channel with independent but non-identically distributed log-normal distributions. The variance of the channel in each layer is a function of scintillation index of the layer. We assume 32-cross quadrature amplitude modulation (XQAM) scheme and derive closed form expression of Average Symbol Error Probability (ASEP). We analyze the ASEP performance of the system for different layers with different intensities of turbulence. As the number of layers or depth increases, the performance degrades. We also present simulation results of ASEP and compare them with their analytical counterparts. A close matching between both validates our analytical approach. Furthermore, we present the performance with 32-rectangular quadrature amplitude modulation (RQAM) scheme with 16 × 2 and 8 × 4 constellations. We observe that the XQAM outperforms the RQAM.
{"title":"Performance Analysis of Vertical Underwater Visible Light Communication System with Cross-QAM","authors":"Chaitanya Chhichhia, Aakarshak Nandwani, Rachna Sharma, Y. Trivedi","doi":"10.1109/NCC55593.2022.9806813","DOIUrl":"https://doi.org/10.1109/NCC55593.2022.9806813","url":null,"abstract":"In this paper, we consider a vertical Underwater Wireless Visible Light Communication (UWVLC) system, where the source is located at the surface of the sea. The distance between both the source and the destination is divided in certain intervals or layers. We assume turbulence in the underwater channel and the intensity of the turbulence, referred in term of scintillation index, varies between consecutive layers. Further, the turbulence based fading channel is modelled by log-normal distribution and the statistics of the channel vary from one layer to another. Thus, we assume cascaded channel with independent but non-identically distributed log-normal distributions. The variance of the channel in each layer is a function of scintillation index of the layer. We assume 32-cross quadrature amplitude modulation (XQAM) scheme and derive closed form expression of Average Symbol Error Probability (ASEP). We analyze the ASEP performance of the system for different layers with different intensities of turbulence. As the number of layers or depth increases, the performance degrades. We also present simulation results of ASEP and compare them with their analytical counterparts. A close matching between both validates our analytical approach. Furthermore, we present the performance with 32-rectangular quadrature amplitude modulation (RQAM) scheme with 16 × 2 and 8 × 4 constellations. We observe that the XQAM outperforms the RQAM.","PeriodicalId":403870,"journal":{"name":"2022 National Conference on Communications (NCC)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115710152","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-05-24DOI: 10.1109/NCC55593.2022.9806727
Ashok Parmar, Kamal M. Captain, Rahul Kumar, Ankit Chouhan
The spectrum sensing based on single detector suffers from adverse effects such as fading, shadowing and hidden node problems. Cooperative spectrum sensing (CSS) is proposed to overcome these effects by utilizing the spatial diversity among the spatially located cooperating secondary users (CSUs). In traditional centralized CSS, the CSUs share their detection results with the fusion center (FC). Based on the information received from the CSUs, the FC analyze the information and takes the final decision on the occupancy of the primary user (PU) channel. Generally, in literature, the reporting channel between CSUs and the FC is assumed to be error free. However, these reporting channels are wireless channels which undergo fading and shadowing resulting in imperfect channels. In this work, we propose a model based on binary erasure channel (BEC) which is more suitable to model the reporting channel between the CSUs and the FC. We then, analyze the performance of the CSS under imperfect reporting channels. We then analyze the performance of repetition code based algorithm to improve the performance of CSS under imperfect reporting channels. It is found that the repetition code based algorithm significantly improves the performance. Also, by properly choosing the repetition length in the repetition based algorithm, the effects of reporting channel errors can be completely removed.
{"title":"On the Performance of Cooperative Spectrum Sensing Under Binary Erasure Reporting Channels","authors":"Ashok Parmar, Kamal M. Captain, Rahul Kumar, Ankit Chouhan","doi":"10.1109/NCC55593.2022.9806727","DOIUrl":"https://doi.org/10.1109/NCC55593.2022.9806727","url":null,"abstract":"The spectrum sensing based on single detector suffers from adverse effects such as fading, shadowing and hidden node problems. Cooperative spectrum sensing (CSS) is proposed to overcome these effects by utilizing the spatial diversity among the spatially located cooperating secondary users (CSUs). In traditional centralized CSS, the CSUs share their detection results with the fusion center (FC). Based on the information received from the CSUs, the FC analyze the information and takes the final decision on the occupancy of the primary user (PU) channel. Generally, in literature, the reporting channel between CSUs and the FC is assumed to be error free. However, these reporting channels are wireless channels which undergo fading and shadowing resulting in imperfect channels. In this work, we propose a model based on binary erasure channel (BEC) which is more suitable to model the reporting channel between the CSUs and the FC. We then, analyze the performance of the CSS under imperfect reporting channels. We then analyze the performance of repetition code based algorithm to improve the performance of CSS under imperfect reporting channels. It is found that the repetition code based algorithm significantly improves the performance. Also, by properly choosing the repetition length in the repetition based algorithm, the effects of reporting channel errors can be completely removed.","PeriodicalId":403870,"journal":{"name":"2022 National Conference on Communications (NCC)","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123966453","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-05-24DOI: 10.1109/NCC55593.2022.9806762
Abhishek K. Gupta, N. Sabu
Molecular communication (MC) can enable nano-scale devices to communicate with each other using molecules as information carriers. To enhance the performance of MC, receiver-devices with multiple receiving ports can be utilized to form single-input multiple-output (SIMO) and multiple-input multiple-output (MIMO) communication links. The receiver ports are analogous to antennas in wireless communication. This paper considers a diffusion-based MC SIMO system with a point transmitter and one receiver system with many receiving ports (RxPs). We first characterize the joint channel between the transmitter and RxPs. We then present the optimal maximum-a-posteriori (MAP) decoding for this system when all ports can share complete information and a central device soft-combines the individual signal values to decode the signal. We then consider a Poisson channel approximation for the channel and show that weighted linear combining is an optimal decoding scheme with weights depending on average channel values. We also study a symmetric SIMO system and investigate the decoding error probability and diversity order for various soft and hard combining schemes.
分子通信(MC)可以使纳米级器件之间利用分子作为信息载体进行通信。为了提高MC的性能，可以利用具有多个接收端口的接收设备组成单输入多输出(SIMO)和多输入多输出(MIMO)通信链路。接收端口类似于无线通信中的天线。本文研究了一种基于扩散的多点发射和多点接收系统的多接收端口(rxp) MC SIMO系统。我们首先描述了发射机和rxp之间的联合信道。然后，我们提出了该系统的最佳最大后验(MAP)解码，当所有端口都可以共享完整的信息，并且中央设备对单个信号值进行软组合以解码信号。然后，我们考虑了信道的泊松信道近似，并表明加权线性组合是一种最优解码方案，其权重取决于平均信道值。我们还研究了对称SIMO系统，并研究了各种软、硬组合方案的译码错误概率和分集顺序。
{"title":"Diversity Combining in a Single-Input-Multiple-Output Molecular Communication System","authors":"Abhishek K. Gupta, N. Sabu","doi":"10.1109/NCC55593.2022.9806762","DOIUrl":"https://doi.org/10.1109/NCC55593.2022.9806762","url":null,"abstract":"Molecular communication (MC) can enable nano-scale devices to communicate with each other using molecules as information carriers. To enhance the performance of MC, receiver-devices with multiple receiving ports can be utilized to form single-input multiple-output (SIMO) and multiple-input multiple-output (MIMO) communication links. The receiver ports are analogous to antennas in wireless communication. This paper considers a diffusion-based MC SIMO system with a point transmitter and one receiver system with many receiving ports (RxPs). We first characterize the joint channel between the transmitter and RxPs. We then present the optimal maximum-a-posteriori (MAP) decoding for this system when all ports can share complete information and a central device soft-combines the individual signal values to decode the signal. We then consider a Poisson channel approximation for the channel and show that weighted linear combining is an optimal decoding scheme with weights depending on average channel values. We also study a symmetric SIMO system and investigate the decoding error probability and diversity order for various soft and hard combining schemes.","PeriodicalId":403870,"journal":{"name":"2022 National Conference on Communications (NCC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122568657","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：