arXiv subjects

Rashmi Kamran

Publications and source records attributed to Rashmi Kamran.

11 recordsLinked to original sources

arXiv2026

Bootstrap-Based Receiver Synchronization and System Discovery in B2X: An Extension of ATSC 3.0

Addressing the increasing and diversified demands of multicast and broadcast services require highly efficient multicast and broadcast technologies. Broadcast networks, such as Advanced Television Systems Committee 3.0 (ATSC 3.0), are inherently designed to support these services and continue to evolve to meet growing performance and scalability requirements. At the same time, smartphones are increasingly used for video streaming and other high-volume services, placing growing pressure on mobile network capacity. Interworking between broadcast and mobile networks is therefore an important enabler for efficient and seamless service delivery. In this context, Broadcast-to-Everything (B2X) extends ATSC 3.0 to support enhanced interoperability with Third Generation Partnership Project (3GPP) mobile systems while maintaining low cross-correlation with ATSC 3.0 bootstrap signals, supporting reliable system identification in scenarios where multiple waveforms may be present. Bootstrap signaling, which enables initial signal detection and synchronization, is a key feature of ATSC-based waveform discovery and synchronization, and B2X further extends this capability through a scalable bootstrap framework supporting a range of bandwidth configurations. This paper investigates system discovery through bootstrap signal detection at the B2X receiver and presents key design-related findings, including parameter selection and cross-testing with ATSC 3.0. We present extensive simulations of the receiver performance under diverse propagation and mobility conditions, ranging from stationary to high-speed scenarios. The results demonstrate the robustness of the B2X bootstrap signaling design across a broad range of channel conditions relevant to multicast and broadcast operation.

eess.SP↗

arXiv2025

ITU-T Y.2325: NGN Evolution Towards Future

International Telecommunications Union (ITU) defined Next Generation Network (NGN) underlies most wireline and wireless packet-based telecommunications networks. A key design principle of NGN is decoupling of service-related functions from the underlying transport stratum, making user services independent of transport technologies. Interestingly, the NGN architecture, as defined in ITU standards, did not follow this design principle for internal network services, e.g., mobility, or authentication though adhering for external user services like IPTV or Multimedia services. These internal services are handled by the NGN transport control plane, making them an intrinsic part of the transport stratum, resulting in a tightly coupled service and transport functionality as opposed to the proclaimed design goal. This design choice may force each transport technology to support internal services individually, e.g., separate authentication service for each transport, leading to duplication. Since the NGN architecture is the base underlying architecture for most packet-based telecommunications network including advanced cellular networks like 4th/5th Generation cellular networks, the limitation persists in these cellular networks as well. To remedy the situation, the decoupling of service and transport can be generalized to include internal services like mobility and authentication also. In this context, the recently published ITU Y.2325 recommendation, defines an evolved NGN architecture, wherein all services, including internal network services, are decoupled from the transport stratum. The proposal results in a more scalable and modular evolved NGN architecture that can be used as a template for all future telecom networks including IMT-2030 (6th generation mobile networks). In this article, we review the evolved NGN architecture, as proposed in ITU-T Y.2325.

cs.NI↗

arXiv2025

Energy-Aware 6G Network Design: A Survey

6th Generation (6G) mobile networks are envisioned to support several new capabilities and data-centric applications for unprecedented number of users, potentially raising significant energy efficiency and sustainability concerns. This brings focus on sustainability as one of the key objectives in the their design. To move towards sustainable solution, research and standardization community is focusing on several key issues like energy information monitoring and exposure, use of renewable energy, and use of Artificial Intelligence/Machine Learning (AI/ML) for improving the energy efficiency in 6G networks. The goal is to build energy-aware solutions that takes into account the energy information resulting in energy efficient networks. Design of energy-aware 6G networks brings in new challenges like increased overheads in gathering and exposing of energy related information, and the associated user consent management. The aim of this paper is to provide a comprehensive survey of methods used for design of energy efficient 6G networks, like energy harvesting, energy models and parameters, classification of energy-aware services, and AI/ML-based solutions. The survey also includes few use cases that demonstrate the benefits of incorporating energy awareness into network decisions. Several ongoing standardization efforts in 3GPP, ITU, and IEEE are included to provide insights into the ongoing work and highlight the opportunities for new contributions. We conclude this survey with open research problems and challenges that can be explored to make energy-aware design feasible and ensure optimality regarding performance and energy goals for 6G networks.

cs.NI↗

arXiv2024

Applying SDN to Mobile Networks: A New Perspective for 6G Architecture

The upcoming Sixth Generation (6G) mobile communications system envisions supporting a variety of use cases with differing characteristics, e.g., very low to extremely high data rates, diverse latency needs, ultra massive connectivity, sustainable communications, ultra-wide coverage etc. To accommodate these diverse use cases, the 6G system architecture needs to be scalable, modular, and flexible; both in its user plane and the control plane. In this paper, we identify some limitations of the existing Fifth Generation System (5GS) architecture, especially that of its control plane. Further, we propose a novel architecture for the 6G System (6GS) employing Software Defined Networking (SDN) technology to address these limitations of the control plane. The control plane in existing 5GS supports two different categories of functionalities handling end user signalling (e.g., user registration, authentication) and control of user plane functions. We propose to move the end-user signalling functionality out of the mobile network control plane and treat it as user service, i.e., as payload or data. This proposal results in an evolved service-driven architecture for mobile networks bringing increased simplicity, modularity, scalability, flexibility and security to its control plane. The proposed architecture can also support service specific signalling support, if needed, making it better suited for diverse 6GS use cases. To demonstrate the advantages of the proposed architecture, we also compare its performance with the 5GS using a process algebra-based simulation tool.

cs.NI↗

arXiv2024

A Flexible Architecture for Broadcast Broadband Convergence in Beyond 5G

There has been an exponential increase in the usage of multimedia services in mobile networks in recent years. To address this accelerating data demand, mobile networks are experiencing a subtle transformation in their architecture. One of the changes in this direction is the support of Multicast/Broadcast Service (MBS) in the Third Generation Partnership Project (3GPP) Fifth Generation (5G) network. The MBS has been introduced to enhance resource utilization and user experience in 3GPP 5G networks. However, there are certain limitations in the 3GPP 5G MBS architecture, such as the selection of the delivery method (unicast or broadcast) by the core network (may result in sub-optimal radio resource utilization) and no provision for converging non-3GPP broadcast technologies (like digital terrestrial television) with cellular (3GPP 5G) broadband. In this context, we propose a new architecture for the convergence of cellular broadband and non-3GPP broadcast networks. A novelty of the architecture is that it treats signalling exchange with User Equipment (UE) as data (service) which results in improved scalability of mobile networks. The architecture supports enhanced flexibility in choosing a delivery method (3GPP 5G unicast, 3GPP 5G broadcast, or non-3GPP broadcast) for user data. We evaluate the performance of the proposed architecture using process algebra-based simulations, demonstrating a significant reduction in the number of signalling messages exchanged between the UE and the network for MBS session establishment as compared to the 3GPP 5G network.

cs.NI↗

arXiv2023

An Architecture for Control Plane Slicing in Beyond 5G Networks

To accommodate various use cases with differing characteristics, the Fifth Generation (5G) mobile communications system intends to utilize network slicing. Network slicing enables the creation of multiple logical networks over a shared physical network infrastructure. While the problems such as resource allocation for multiple slices in mobile networks have been explored in considerable detail in the existing literature, the suitability of the existing mobile network architecture to support network slicing has not been analysed adequately. We think the existing 5G System (5GS) architecture suffers from certain limitations, such as a lack of slice isolation in its control plane. This work focuses on the future evolution of the existing 5GS architecture from a slicing perspective, especially that of its control plane, addressing some of the limitations of the existing 5GS architecture. We propose a new network architecture which enables efficient slicing in beyond 5G networks. The proposed architecture results in enhanced modularity and scalability of the control plane in sliced mobile networks. In addition, it also brings slice isolation to the control plane, which is not feasible in the existing 5G system. We also present a performance evaluation that confirms the improved performance and scalability of the proposed system viz a viz the existing 5G system.

cs.NI↗

arXiv2020

All-Analog Adaptive Equalizer for Coherent Data Center Interconnects

In a high-speed coherent optical transmission system, typically the signals obtained at the receiver front-end are digitized using very high-speed ADCs and then processed in the digital domain to remove optical channel impairments. In this work, we show that these signals can instead be processed in the analog domain itself, which can significantly reduce the power consumption as well as the complexity of the receiver. The first all-analog adaptive equalizer for receivers of coherent dual-polarization optical links has been presented with its detailed architecture and measurement results. The proof-of-concept equalizer uses the constant modulus algorithm for blind adaptation of its weight coefficients to implement a 4x4 2-tap FIR filter in 130 nm SiGe BiCMOS technology. Its functionality is evaluated experimentally for 40 Gb /s data rate and 10 km standard single-mode fiber channel. This demonstration shows that the use of all-analog processing for short-reach data-center interconnects is feasible and is a much simpler solution than the use of the high-speed ADC+DSP based approach. Moreover, when implemented in advanced CMOS or FinFET technologies, the power consumption of the equalizer is expected to be significantly lower than the DSP based implementations in similar process technologies.

eess.SP↗

arXiv2019

Demonstration of an LO-less, DSP-free QPSK Receiver for Data Center Interconnects

We present the first demonstration of a local oscillator (LO)-less digital signal processing (DSP)-free coherent receiver for high-capacity short distance optical links. Experimental results with an analog domain constant modulous algorithm (CMA)-based equalizer chip for the self-homodyne quadrature phase shift keying (SH-QPSK) system validate the employability of an all-analog and LO-less receiver for low-power interconnects.

eess.SP↗

arXiv2019

High-Capacity Coherent DCIs using PolMuxed Carrier and LO-Less Receiver

A PAM4 based direct detection system has been standardized for short-distance data center interconnects because of its simple architecture. Performance of the PAM4 systems is limited for high dispersion values or demands complicated signal processing for further increase in data rates. A polarization multiplexed carrier based self-homodyne (PMC-SH) link with adaptive polarization control is a practical approach with an laser oscillator (LO)-less and carrier phase recovery (CPR)-free coherent receiver that can replace PAM4 links for achieving high data rates. We analytically find that PMC-SH scheme results in a significantly better BER for a given transmission rate or can achieve doubling of the data rate for given bandwidth of electronics and laser power (when compared with PAM4). Practical implementation of the proposed system with adaptive polarization control is also discussed. Presented theoretical frame work highlights the advantages of such self-homodyne systems over PAM4 based systems in terms of SNR requirements and capacity.

eess.SP↗

arXiv2018

A Polarization Multiplexed Carrier based Coherent Link with Adaptive Polarization Control

Transmitting polarization multiplexed carrier makes the receiver of a coherent system local oscillator-less and frequency offset-free. A polarization multiplexed carrier based self-homodyne (PMC-SH) system with an adaptive polarization control (PC) can replace pulse amplitude modulation (PAM- 4) data center interconnects. An adaptive PC technique is practically implemented by using an electrically controlled PC along-with control circuitry for PMC-SH systems. The de-multiplexing of the carrier and the modulated signal by using this technique is validated through simulations for a 50 Gbaud PMC-SH quadrature phase shift keying (QPSK) system with 20km standard single mode fiber (SSMF). We successfully demonstrate 16 Gbaud PMC-SH systems with adaptive PC for 10km SSMF channel. A bit error rate (BER) of 5.9 x 10^(-5) is achieved with 32 Gb/s PMC-SHQPSK system without any signal processing while a BER of 8.7 x 10^(-3) is achieved with a 64 Gb/s PMC-SH quadrature amplitude modulation (16QAM) system after equalization.

eess.SP↗

arXiv2018

Adaptive Polarization Control for Coherent Optical Links with Polarization Multiplexed Carrier

Self-homodyne systems with polarization multiplexed carrier offer an LO-less coherent receiver with simplified signal processing requirement that can be a good candidate for high-speed short-reach data center interconnects. The practical implementation of these systems is limited by the requirement of polarization control at the receiver end for separating the carrier and the modulated signal. In this paper, effect of polarization impairments in polarization diversity based systems is studied and modeled. A novel and practical adaptive polarization control technique based on optical power feedback from one polarization is proposed for polarization multiplexed carrier based systems and verified through simulation results. The application of the proposed concept is experimentally demonstrated also for a QPSK system with polarization multiplexed carrier.

eess.SP↗