Interleave Division Multiple Access Scheme Research Articles

Progressive pattern orthogonal interleaver set for interleave division multiple access based, non orthogonal multiple access schemes: Beyond 5G perspective

Abstract This communication suggests an orthogonal interleaver set for interleave division multiple access (IDMA) based non orthogonal multiple access (NOMA) schemes from beyond 5G viewpoint to support enormous increase in user count. The method generates an orthogonal interleaver set by providing two mother interleavers as seed to generate other users’ interleaving patterns progressively. The key feature of the proposed scheme is that it reduces implementation complexity and memory requirement at the base station, while implementing iterative multiuser detection (MUD), which most of the interlaever designs suggested in literature do not consider. It provides additional security to the user data due to progressively changing mother interleavers’ pattern along with the conventional purpose of providing unique identity for individual users in the system. The proposed orthogonal interleaver set is tested through simulations under multiple IDMA system configurations. It has been observed that it preserves the bit error rate (BER) performance of the IDMA scheme along with the optimal implementation complexity and minimal information exchange requirement between base station and mobile station to share the interleaver design.

Performance Analysis of MITA Interleaver on Hybrid Systems using Diversity

The demands of 5 thgeneration communication devices such as greater throughput, coverage and reliability cannot be easily met by any one physical media. Recently, wireless and powerline channels were combined and diversity techniques were employed to improve reliability using only the OFDM technique. In this paper, the hybrid system with diversity techniques is implemented and evaluated using Interleave Division Multiple Access (IDMA) scheme. As the strength of the IDMA scheme heavily relies on the adapted interleaving algorithm, in the paper interleaving algorithms such as Random, Tree and recently proposed Multiplicative Interleaving with Tree Algorithm (MITA) interleavers are compared on the grounds of computation complexity, memory occupied and bit error rate (BER). For analysis of BER, over MATLAB environment, the hybrid system assumes Rayleigh fading channel and Additive White Gaussian Noise (AWGN) on wireless medium and Symmetric alpha stable (SαS) noise on powerline channel. The outcome of comparison parameters verifies the superior performance of MITA interleaver in a hybrid system over the IDMA scheme.

On the performance of modulo based Deci power interleaver in code domain NOMA system

Non-orthogonal multiple access (NOMA) is the potential multiple access considered for next generation (5G/6G) mobile communication and most of the research papers have been focused on power-domain NOMA. However, this research paper makes an effort to contribute to understand another aspect of NOMA i.e. code domain NOMA due to its better performance in large system where number of resources and users grows unboundedly. Interleave division multiple access (IDMA) is an established framework for code domain implementation of NOMA transmission and the performance of IDMA depends greatly on the interleavers as they are used to distinguish among the users. So, a unique Deci power interleaver (DPI) has been proposed and analyzed in this paper for the suggested IDMA scheme. The proposed interleaver is based on modulo operation, which reduce the bandwidth requirement and computational complexity without any performance degradation. Simulation experiments have been carried out to compare the DPI with random and other interleavers with coded and uncoded scenario in IDMA system.

MMSE Equalization Based Performance of Chaotic Interleaving Scheme for Iterative IDMA System

Background: In this paper, a chaotic interleaving scheme is proposed for further performance improvement of Interleave Division Multiple Access (IDMA). Interleavers are used to generate permuted sequence of signals to be transmitted with optimum correlation. Methods: Random interleaving (RI) was the fundamental taxonomy and used to distinguish the different users in IDMA scheme. The logistic map based chaotic interleaving scheme is suggested for IDMA. The system is also combined with Minimum Mean Square Error (MMSE) equalizer to combat the effect of Inter Symbol Interference (ISI). Results: For the sake of simplicity, no pulse shaping is assumed at the transmitter and ISI channel is considered to be a fixed 3 tap channel. Simulations are performed in MATLAB. BPSK modulation is used. Furthermore, the results show that the IDMA with proposed logistic map based chaotic interleaver outperforms the traditional random interleaving scheme in terms of BER without the need of extra memory and computational complexity. Conclusion: The obtained results show the noticeable performance improvement of CI-IDMA with MMSE equalization in deep fading situations. Chaos based interleaver also offers other advantages such as less requirement of memory and small implementation complexity.

Analysis and design of tent map interleaver for interleave division multiple access scheme

Analysis and design of tent map interleaver for interleave division multiple access scheme

Analysis and design of tent map interleaver for interleave division multiple access scheme

Interleavers are the main component of almost all multiple access systems, such as Code Division Multiple Access (CDMA) and Interleave Division Multiple Access (IDMA henceforth). In IDMA systems, interleavers are crucially important for user separation that consequently also contributes maximising the system throughput. The paper intends to claim an efficient Tent map based design of interleaver (TMI henceforth) generation which has less computational complexity and is more efficient in bandwidth compared to the existing prevailing algorithms in the domain. The proposed scheme is based on chaos theory and the simulation results show that TMI based IDMA can achieve the good BER performance without the need of extra memory resources.

Flip left-right approach based novel inverse tree interleavers for IDMA scheme

In this paper, a novel inverse-tree interleaver (ITI) has been proposed for Interleave-Division Multiple-Access (IDMA) scheme. The generation of this interleaver is based on flip left-right approach. The origin of ITI generation technique is motivated from tree-based interleavers used in IDMA. This novel interleaver offers reduction in memory requirement without any significant compromise in the performance. A novel concept of user range parameter has been introduced for determining computation complexity of ITI for each user. The paper also deals with the performance analysis of uncoded IDMA in presence of ITI under Additive White Gaussian Noise (AWGN) channel. A comparison of ITI with other major existing interleavers has been performed for the same channel environment.

Performance of coded STBC-IDMA system using polarization diversity for downlink transmission

In this paper, we evaluate error-rate (ER) performance of downlink turbo coded interleave division multiple access scheme using dual-polarized space---time transmit diversity. We realize STBC architecture using dual-polarized antenna at base station. At each mobile station (MS), we implement dual-polarized structure to obtain compact destination devices. Further, we model polarizing system considering transmit and receive correlations and cross-polarization discrimination. We incorporate log-MAP decoding algorithm at each MS to offer better BER performance. In particular, we explicate STBC-IDMA system's performance with polarization diversity for a genuine channel model using Stanford University Interim model and long-term evolution channel specifications. From our simulation results, we observe that even though our considered system with dual-polarized antenna require higher SNR to produce the same ER as compared to the spatially-separated antenna, it achieves the advantage of MIMO gain with compact size of MS.

High-Speed Detection with Avalanche Photodiode in Optical Interleave Division Multiple Access Scheme

Objective: To execute the Avalanche photodiode instead of a PIN photodiode in Optical Interleave Division multiple Access (O-IDMA) communication system and to analyze the performance for high data rate transmission. Methods/Statistical Analysis: The detection of optical signal at the receiver of the O-IDMA system is an important operation and decides the performance of the system. Here the detection is done using Avalanche Photodiode for O-IDMA system and analyzed. Iterative decoder is used for decoding at the receiver using the soft decision method. MATLAB is utilized as a simulation tool. Findings: The simulation results have been demonstrated that Avalanche Photodiode is appropriate than PIN Photodiode. The completion and efficiency of the O-IDMA system can be ameliorated with the utilization of avalanche photo detector. Applications/Improvements: The completion of the O-IDMA system is ameliorated appreciably by utilizing Avalanche photodiode and system support more no. of users, less bit error rate and large data rate transmission.Keywords: Avalanche Photodiode, Bit Error Rate, IDMA Scheme, Optical Fiber, PIN Photodiode

Performance Evaluation of Diversity Techniques in IDMA Scheme for Next Generation (4G) in Underwater Wireless Communication

This paper provides a review on the diversity techniques of IDMA (Interleave Division Multiple Access) technology in underwater wireless IDMA employs interleavers as the only means in order to distinguish the users. This paper provides a comprehensive study of diversity techniques in IDMA scheme to mitigate the fading issue. In this paper, we compare the different generation diversity techniques in IDMA scheme on computational complexity, bit error rate and memory requirement. Recent advancement in underwater communication is modulation techniques, multiplexing techniques and multiple access techniques. Underwater communication channel is characterized.

IDMA Based Anti-collision in RFID Networks

Even though object identification is its main objective, it is generally accepted that there are some technological challenges that should be addressed in order to exploit the full potential of RFID (Radio frequency identification). The anti-collision problem is one of them. Despite the different proposed methods, it still needs further study on how to improve identification ability. This paper presents a novel algorithm with IDMA (Interleave division multiple access) scheme to resolve the anti-collision problem for RFID. IDMA, which is one of the most promising technologies for high data rate wireless systems, can be regarded as a special case of CDMA (Code division multiple access). In contrast to CDMA, which separates tags by signatures or spreading codes, distinct interleavers are the only means to separate tags for IDMA. In this paper, a RFID based IDMA receiver is proposed and compared to classical systems. Simulation results demonstrate that this system provides an improvement in performance in terms of bit error rate in dense scenarios (large number of tags) and it offers an efficient alternative to systems with classical spreading sequence.

Optimal Spreading Mechanism with Different Modulation Techniques Using Random Interleaver in IDMA System

The Interleave-Division Multiple-Access (IDMA) scheme is known for property of orthogonality amongst its user-specific interleavers. The interleavers are, therefore, referred has the core heart of IDMA Transceivers. Now-adays, the IDMA scheme is being thought as a strongest candidate for radio access in cellular mobile communication systems. It is attractive for wireless access due to its numerous advantages over TDMA, FDMA and CDMA and other multiple access schemes. In this paper, IDMA system is being simulated using random interleaver foe each user. On comparing various spreading techniques including repition, Gold code and Walsh code spreading, it is observed from simulation results, that the performance is almost similar for all the spreading mechanisms. However, from implementation point of view, repition spreading is concluded as optimum mechanism because it requires less memory, less computational complexity, easy implementation and also defines larger number of users as compared to Gold code and Walsh code for same spreading length. In this paper, the performance analysis of iterative IDMA receivers have been evaluated with BPSK & QPSK modulation techniques employing random interleavers in uncoded and rate ½ convolutional coded conditions with Additive White Gaussian Noise (AWGN) channel. During the simulation, it has been observed that IDMA system with QPSK modulation techniques employing QPSK outperforms its counterpart BPSK optimally.

Rotational Interleaver for Iterative Interleave-Division Multiple-Access Scheme

In iterative IDMA scheme, the users are distinguished with various chip-level interleaving sequences instead of user-specific signature sequences as in conventional code-division multiple-access (CDMA) scheme. A set of interleavers is considered to be practical if it has zero correlation with each other and also easy to generate as well requires minimal bandwidth during communication process. A properly defined correlation between user-specific interleavers can be utilized to formulate a minimal collision criterion, where zero-correlation (i.e., orthogonality) implies no collision. In this paper, a practical interleaver has been proposed for interleave-division multiple-access (IDMA) systems. Simulation results show that the proposed interleaver performs even better to random interleavers initially reported for iterative IDMA system.

Analysis of Orthogonal Interleavers with Iterative IDMA Scheme

Few basic requirements for future wireless 4G systems includes low receiver cost, decentralized (i.e. asynchronous) control, simple treatment of ISI, cross cell interference mitigation, diversity against fading, power efficiency (long battery life), multimedia services, high user number, high throughput and high spectral efficiency. All theses factors mentioned are not fulfilled by any multiple access techniques at present. Interleave-Division Multiple-Access (IDMA) is a technique, which provides better result during simulation when applied with at least few of the future mobile communication requirements. IDMA employs interleavers as the only means in order to distinguish the users. This paper provides a comprehensive study of IDMA technique with orthogonal interleavers.

Analysis and design of optimum interleaver for iterative receivers in IDMA scheme

AbstractIn this paper, we propose a new tree based interleaver (TBI) to generate different chip‐level interleaving sequences for different users in an interleave division multiple access (IDMA) system, which reduces computational complexity. This method of generation also solves the memory cost problem and reduces the amount of information exchange between mobile stations (MSs) and base stations (BSs) required to specify the interleaver. Simulation results are presented to show that the proposed interleavers perform well as compared to random interleavers in an IDMA system. Copyright © 2008 John Wiley & Sons, Ltd.

Hybrid orthogonal/random multiple access scheme with improved performance for downlink CDMA systems

In this paper, a hybrid orthogonal and random multiple access scheme with improved performance for capacity-enhanced downlink Code-Division Multiple-Access (CDMA) systems is presented, which is in fact a combination of the conventional orthogonal spreading scheme and the synchronous Interleave Division Multiple Access (IDMA) scheme. The proposed scheme can achieve near single user performance for very large number of users by the iterative turbo like detection. Analysis and simulation results show that the proposed scheme performs better than the synchronous IDMA scheme for the same time complexity. Meanwhile, larger capacity can be provided compared with the conventional orthogonal schemes.

A multicarrier interleave-division uwb system

We propose a multicarrier interleave-division multiple-access scheme for ultra-wideband wireless communications. For the uplink, a chip-level interleaving method at the transmitter with a simple turbo receiver is proposed to effectively suppress the frequency-selective fading and multiple-access interference. Both hard and soft frequency notching methods are suggested to suppress the narrowband interference. For the downlink, a two-layer interleaving scheme is proposed, in which data from different users are separated in the frequency-domain while the different data streams for the same user are separated in the interleaver-domain. A joint power and subcarrier allocation algorithm is developed to exploit the multiuser diversity and thereby improve the system performance. The performance of the proposed system is evaluated by both theoretic analysis and simulations. It is seen that within a few iterations, the proposed system exhibits single-user performance even under over-loaded conditions

Interleave division multiple-access

This paper provides a comprehensive study of interleave-division multiple-access (IDMA) systems. The IDMA receiver principles for different modulation and channel conditions are outlined. A semi-analytical technique is developed based on the density evolution technique to estimate the bit-error-rate (BER) of the system. It provides a fast and relatively accurate method to predict the performance of the IDMA scheme. With simple convolutional/repetition codes, overall throughputs of 3 bits/chip with one receive antenna and 6 bits/chip with two receive antennas are observed for IDMA systems involving as many as about 100 users.