Ravi Maddila | Malaviya National Institute of Technology, Jaipur (original) (raw)

Papers by Ravi Maddila

Research paper thumbnail of A new multi wavelength — Optical Code Division Multiple Access code design based on Balanced Incomplete Block Design

2007 International Conference on Industrial and Information Systems, 2007

A new three-dimensional (Space/ Wavelength/ Time) Multi Wavelength Optical Code Division Multiple... more A new three-dimensional (Space/ Wavelength/ Time) Multi Wavelength Optical Code Division Multiple Access (MW-OCDMA) code design based on Balanced Incomplete Block Designs (BIBD) is proposed for fiber optic communication. The proposed code has a weight of W = s × w × k, where s is the number of fibers (space) used per user, w is the number of wavelengths used per user and k is the number of ones in a block of BIBD. This code ensures a maximum cross-correlation of '1' between any two users. The cardinality of the code family is higher by a factor of approximately '3' when compared with BIBD codes of one-dimensional OCDMA with equivalent weight, length and cross-correlation.

Research paper thumbnail of Design and analysis of zero-gap directional coupler-based mode separator

This paper addresses the design of mode separator in a zero-gap directional coupler by using effe... more This paper addresses the design of mode separator in a zero-gap directional coupler by using effective index based matrix method for Titanium: Lithium Niobate (Ti:LiNbO3) technology. The total length of the device is 15 mm, which separates TE and TM modes at 1.3 μm wavelength with a crosstalk less than -31dB.

Research paper thumbnail of Design and analysis of new code families for three-dimensional OCDMA

2008 2nd International Symposium on Advanced Networks and Telecommunication Systems, 2008

ABSTRACT Abstract-A new code design algorithm for application in three-dimensional (3-D) Optical ... more ABSTRACT Abstract-A new code design algorithm for application in three-dimensional (3-D) Optical Code Division Multiple Access (OCDMA) for asynchronous optical fiber communication is proposed. In this paper, 3-D refers to space-wavelength-time spreading. The performance analysis of the proposed algorithm in 3-D Multiple Pulses per Plane codes is shown. This design ensures a maximum cross-correlation of 1 between any two codes. The performance metrics that have been investigated are bit error rate due to Multiple Access Interference for varying number of simultaneous users and, cardinality for different values of temporal length.

Research paper thumbnail of Design and analysis of three-dimensional OCDMA code families

Optical Switching and Networking, 2009

A new code design algorithm for application in three-dimensional (3D) optical code division multi... more A new code design algorithm for application in three-dimensional (3D) optical code division multiple access (OCDMA) for asynchronous optical fiber communication is proposed. 3D refers to space-wavelength-time codes. The performance analysis of the proposed algorithm in 3D multiple pulses per plane (MPP) codes is shown. This design ensures a maximum cross-correlation of '1' between any two codes. The performance metrics that have been investigated are the bit error rate due to multiple access interference (MAI) for different values of the number of simultaneous users and, cardinality for different values of temporal length.

Research paper thumbnail of Design and performance analysis of code families for multi-dimensional optical CDMA

IET Communications, 2009

A code design algorithm for application in Multi-Dimensional Optical Code Division Multiple Acces... more A code design algorithm for application in Multi-Dimensional Optical Code Division Multiple Access (MD-OCDMA) for asynchronous optical fibre communication is proposed. Two-dimensional (2-D) wavelength-time or space-time OCDMA and three-dimensional (3-D) space-wavelength-time OCDMA are subsets of MD-OCDMA. Some applications and the performance analysis of the algorithm in 2-D multipulse per row codes and 3-D multipulse per plane codes are shown. In the applications discussed, this design ensures a maximum crosscorrelation of '1' between any two codes. The performance metrics studied are the probability of error due to multiple access interference for different numbers of 1 active users and optimum temporal length for different values of cardinality. The performance analysis shows that the proposed 2-D design offers very low probability of error due to multiple access interference at lower cardinality when compared with other 2-D designs using equivalent code dimension. A comparison of the proposed 3-D design with an existing 3-D design shows better performance at lower cardinality. The 3-D designs show better performance when compared with the 2-D designs. 1 Introduction Optical Code Division Multiple Access (OCDMA) is one of the competing technologies for future multiple access networks along with Wavelength Division Multiple Access and Optical Time Division Multiple Access. The concept of assigning spreading codes to each user in a fibre optic communication network is used in OCDMA. A user transmits an assigned code whenever a '1' is to be transmitted and does not transmit anything whenever a '0' is to be transmitted. The major advantage of OCDMA is asynchronous communication, which considerably reduces optical resources required for timing recovery. Codes for OCDMA systems employing intensity detection have to be unipolar, orthogonal (minimum cross-correlation) and constant weight to obtain low values of probability of error due to Multiple Access Interference (MAI). Hence, a family of codes called Optical Orthogonal Codes (OOCs) [1-3] have been designed. An OOC code family is represented as (T, K, λ a , λ c), where T is the temporal length of the code family, K is the weight of the code family, i.e., the number of ones in each code, λ a is

Research paper thumbnail of A Review of Non-Invasive HbA1c and Blood Glucose Measurement Methods

2021 IEEE International Symposium on Smart Electronic Systems (iSES) (Formerly iNiS), 2021

Hemoglobin is a protein in Red Blood Cells (RBC) which supplies oxygen to the human body. A perso... more Hemoglobin is a protein in Red Blood Cells (RBC) which supplies oxygen to the human body. A person’s hemoglobin becomes glycosylated as per the increase in the level of blood sugar. Glycated hemoglobin (HbA1c) is a widely used measure of glycemic control which measures the glucose attached to hemoglobin. Different methods are adopted and utilized for the measurement of HbA1c. Several invasive methods are widely used in pathological laboratories across the globe. The current status of non-invasive HbA1c and blood glucose measurement techniques is summarized in this paper.

Research paper thumbnail of Construction and Generation of OCDMA Code Families using a Complete Row-Wise Orthogonal Pairs Algorithm

A new code construction algorithm for incoherent Multi-Dimensional Optical Code Division Multiple... more A new code construction algorithm for incoherent Multi-Dimensional Optical Code Division Multiple Access (MD-OCDMA) for asynchronous fiber optic communication is proposed. We refer multi-dimensionality to two-dimensional (2D) wavelength-time or space-time domains and three-dimensional (3D) space-wavelength-time domains. The application of the algorithm in constructing 2D multiple pulses per row codes and 3D multiple pulses per plane codes is given. The performance of the codes is discussed. In the applications discussed, this construction ensures a maximum crosscorrelation of 1 between any two codes. The proposed codes have complete 1D code allocation, which increases the cardinality. The performance of some codes in literature is compared with the proposed codes. The analyzed performance measure is bit error rate due to multiple access interference for different numbers of active users. The performance analysis shows that the proposed 2D construction offers very low bit error rate at lower spectral efficiency when compared with other 2D constructions. A comparison of the proposed 3D construction with existing 3D constructions shows lower bit error rate for equivalent code dimension. New integrated optic designs for the generation of OCDMA codes using titanium indiffused lithium niobate technology is explored, which can enable compact encoders and decoders for computer communications.

Research paper thumbnail of A new multi wavelength — Optical Code Division Multiple Access code design based on Balanced Incomplete Block Design

2007 International Conference on Industrial and Information Systems, 2007

A new three-dimensional (Space/ Wavelength/ Time) Multi Wavelength Optical Code Division Multiple... more A new three-dimensional (Space/ Wavelength/ Time) Multi Wavelength Optical Code Division Multiple Access (MW-OCDMA) code design based on Balanced Incomplete Block Designs (BIBD) is proposed for fiber optic communication. The proposed code has a weight of W = s × w × k, where s is the number of fibers (space) used per user, w is the number of wavelengths used per user and k is the number of ones in a block of BIBD. This code ensures a maximum cross-correlation of '1' between any two users. The cardinality of the code family is higher by a factor of approximately '3' when compared with BIBD codes of one-dimensional OCDMA with equivalent weight, length and cross-correlation.

Research paper thumbnail of Design and analysis of zero-gap directional coupler-based mode separator

This paper addresses the design of mode separator in a zero-gap directional coupler by using effe... more This paper addresses the design of mode separator in a zero-gap directional coupler by using effective index based matrix method for Titanium: Lithium Niobate (Ti:LiNbO3) technology. The total length of the device is 15 mm, which separates TE and TM modes at 1.3 μm wavelength with a crosstalk less than -31dB.

Research paper thumbnail of Design and analysis of new code families for three-dimensional OCDMA

2008 2nd International Symposium on Advanced Networks and Telecommunication Systems, 2008

ABSTRACT Abstract-A new code design algorithm for application in three-dimensional (3-D) Optical ... more ABSTRACT Abstract-A new code design algorithm for application in three-dimensional (3-D) Optical Code Division Multiple Access (OCDMA) for asynchronous optical fiber communication is proposed. In this paper, 3-D refers to space-wavelength-time spreading. The performance analysis of the proposed algorithm in 3-D Multiple Pulses per Plane codes is shown. This design ensures a maximum cross-correlation of 1 between any two codes. The performance metrics that have been investigated are bit error rate due to Multiple Access Interference for varying number of simultaneous users and, cardinality for different values of temporal length.

Research paper thumbnail of Design and analysis of three-dimensional OCDMA code families

Optical Switching and Networking, 2009

A new code design algorithm for application in three-dimensional (3D) optical code division multi... more A new code design algorithm for application in three-dimensional (3D) optical code division multiple access (OCDMA) for asynchronous optical fiber communication is proposed. 3D refers to space-wavelength-time codes. The performance analysis of the proposed algorithm in 3D multiple pulses per plane (MPP) codes is shown. This design ensures a maximum cross-correlation of '1' between any two codes. The performance metrics that have been investigated are the bit error rate due to multiple access interference (MAI) for different values of the number of simultaneous users and, cardinality for different values of temporal length.

Research paper thumbnail of Design and performance analysis of code families for multi-dimensional optical CDMA

IET Communications, 2009

A code design algorithm for application in Multi-Dimensional Optical Code Division Multiple Acces... more A code design algorithm for application in Multi-Dimensional Optical Code Division Multiple Access (MD-OCDMA) for asynchronous optical fibre communication is proposed. Two-dimensional (2-D) wavelength-time or space-time OCDMA and three-dimensional (3-D) space-wavelength-time OCDMA are subsets of MD-OCDMA. Some applications and the performance analysis of the algorithm in 2-D multipulse per row codes and 3-D multipulse per plane codes are shown. In the applications discussed, this design ensures a maximum crosscorrelation of '1' between any two codes. The performance metrics studied are the probability of error due to multiple access interference for different numbers of 1 active users and optimum temporal length for different values of cardinality. The performance analysis shows that the proposed 2-D design offers very low probability of error due to multiple access interference at lower cardinality when compared with other 2-D designs using equivalent code dimension. A comparison of the proposed 3-D design with an existing 3-D design shows better performance at lower cardinality. The 3-D designs show better performance when compared with the 2-D designs. 1 Introduction Optical Code Division Multiple Access (OCDMA) is one of the competing technologies for future multiple access networks along with Wavelength Division Multiple Access and Optical Time Division Multiple Access. The concept of assigning spreading codes to each user in a fibre optic communication network is used in OCDMA. A user transmits an assigned code whenever a '1' is to be transmitted and does not transmit anything whenever a '0' is to be transmitted. The major advantage of OCDMA is asynchronous communication, which considerably reduces optical resources required for timing recovery. Codes for OCDMA systems employing intensity detection have to be unipolar, orthogonal (minimum cross-correlation) and constant weight to obtain low values of probability of error due to Multiple Access Interference (MAI). Hence, a family of codes called Optical Orthogonal Codes (OOCs) [1-3] have been designed. An OOC code family is represented as (T, K, λ a , λ c), where T is the temporal length of the code family, K is the weight of the code family, i.e., the number of ones in each code, λ a is

Research paper thumbnail of A Review of Non-Invasive HbA1c and Blood Glucose Measurement Methods

2021 IEEE International Symposium on Smart Electronic Systems (iSES) (Formerly iNiS), 2021

Hemoglobin is a protein in Red Blood Cells (RBC) which supplies oxygen to the human body. A perso... more Hemoglobin is a protein in Red Blood Cells (RBC) which supplies oxygen to the human body. A person’s hemoglobin becomes glycosylated as per the increase in the level of blood sugar. Glycated hemoglobin (HbA1c) is a widely used measure of glycemic control which measures the glucose attached to hemoglobin. Different methods are adopted and utilized for the measurement of HbA1c. Several invasive methods are widely used in pathological laboratories across the globe. The current status of non-invasive HbA1c and blood glucose measurement techniques is summarized in this paper.

Research paper thumbnail of Construction and Generation of OCDMA Code Families using a Complete Row-Wise Orthogonal Pairs Algorithm

A new code construction algorithm for incoherent Multi-Dimensional Optical Code Division Multiple... more A new code construction algorithm for incoherent Multi-Dimensional Optical Code Division Multiple Access (MD-OCDMA) for asynchronous fiber optic communication is proposed. We refer multi-dimensionality to two-dimensional (2D) wavelength-time or space-time domains and three-dimensional (3D) space-wavelength-time domains. The application of the algorithm in constructing 2D multiple pulses per row codes and 3D multiple pulses per plane codes is given. The performance of the codes is discussed. In the applications discussed, this construction ensures a maximum crosscorrelation of 1 between any two codes. The proposed codes have complete 1D code allocation, which increases the cardinality. The performance of some codes in literature is compared with the proposed codes. The analyzed performance measure is bit error rate due to multiple access interference for different numbers of active users. The performance analysis shows that the proposed 2D construction offers very low bit error rate at lower spectral efficiency when compared with other 2D constructions. A comparison of the proposed 3D construction with existing 3D constructions shows lower bit error rate for equivalent code dimension. New integrated optic designs for the generation of OCDMA codes using titanium indiffused lithium niobate technology is explored, which can enable compact encoders and decoders for computer communications.