Exploració per tema "Code division multiple access"
Ara es mostren els items 1-20 de 78
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A combined polling and ISMA-DS/CDMA protocol to provide QoS in packet mobile communications systems
(Institute of Electrical and Electronics Engineers (IEEE), 2000)
Text en actes de congrés
Accés obertThis paper presents a new mechanism that combines the flexibility of an access protocol such as ISMA-DS/CDMA with the ability of a polling mechanism to provide a specific bound for the access delay. This protocol is proposed ... -
A direct-sequence spread-spectrum super-regenerative receiver
(Institute of Electrical and Electronics Engineers (IEEE), 2000)
Comunicació de congrés
Accés obertCurrent applications of the super-regenerative receiver use narrowband modulations. In this paper a new architecture that allows incoherent detection of spread-spectrum signals is presented. A pseudorandom code generator ... -
A dynamic non-singleton fuzzy logic system for DS/CDMA communications
(Institute of Electrical and Electronics Engineers (IEEE), 1998)
Text en actes de congrés
Accés obertWe investigate a dynamic fuzzy logic system, specifically, its non-singleton generalization, and derive a novel adaptive fuzzy line enhancer that successfully solves the non-linear problem of narrowband interference (NBI) ... -
A fast OFDM-CDMA user demultiplexing architecture
(Institute of Electrical and Electronics Engineers (IEEE), 2000)
Text en actes de congrés
Accés obertA fast algorithm based on a butterfly structure is presented that demultiplexes the symbols of a particular type of MC-MA (multi-carrier multiple-access) modulation previously proposed for indoor radio communications. A ... -
A generic radio channel emulator to evaluate higher layer protocols in a CDMA system
(Institute of Electrical and Electronics Engineers (IEEE), 2000)
Text en actes de congrés
Accés obertCurrently, we are involved in the standardisation process to specify the next mobile system generation. A wideband code division multiple access (WCDMA) system is considered in most of the region versions. It would be very ... -
A mobile controlled algorithm for improving the throughput in a s-aloha ds-cdma system
(Institute of Electrical and Electronics Engineers (IEEE), 1996)
Text en actes de congrés
Accés obertThis paper presents a novel adaptive DS-CDMA slotted-ALOHA packet random access scheme with transmitter-based spreading codes for mobiles. It is aimed at improving the throughput and message delay delivery when traffic ... -
A near-optimum MAC protocol based on the distributed queueing random access protocol (DQRAP) for a CDMA mobile communication system
(IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 2000-09)
Article
Accés obertThis paper presents and analyzes a new near-optimum medium access control (MAC) protocol. The proposed access scheme is suitable for a CDMA mobile communication environment, and keeps under control and upper bounded the ... -
A near-optimum mac protocol based on the distributed queueing random access protocol (dqrap) for a cdma mobile communication system
(2000-09)
Article
Accés obertThis paper presents and analyses a new near– optimum random access protocol. The proposed access scheme is suitable for a CDMA environment and minimises the total number of spreading codes needed to achieve a certain ... -
A novel approach to security enhancement of chaotic DSSS systems
(Institute of Electrical and Electronics Engineers (IEEE), 2016)
Text en actes de congrés
Accés obertIn this paper, we propose a novel approach to the enhancement of physical layer security for chaotic direct-sequence spread-spectrum (DSSS) communication systems. The main idea behind our proposal is to vary the symbol ... -
A probabilistic method for blind multiuser detection using array observations
(IEEE, 1997)
Text en actes de congrés
Accés obertIn this paper, a blind algorithm for detecting active users in a DS-CDMA system is presented. This probabilistic algorithm relies on the theory of hidden Markov models (HMM) and is completely blind in the sense that no ... -
A proposal for an adaptive s-aloha access system for a mobile cdma environment
(1998-08)
Article
Accés obertThis paper presents a novel adaptive direct-sequence code-division multiple-access (DS-CDMA) slotted-ALOHA (S-ALOHA) packet random-access scheme with transmitter-based spreading codes for mobiles. It is aimed at improving ... -
A radio channel emulator for WCDMA, based on the hidden Markov model (HMM)
(Institute of Electrical and Electronics Engineers (IEEE), 2000)
Text en actes de congrés
Accés obertOne of the main development and research subjects within the telecommunications area activity is the 3G mobile systems standardisation. The radio access is, of course, the main trouble in mobile systems, so it is important ... -
Adaptive S-ALOHA CDMA as an alternative way of integrating services in mobile environments
(IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 2000-05)
Article
Accés obertCode-division multiple-access (CDMA) schemes appear to be very promising access techniques for coping with the requirements of third-generation mobile systems, mainly because of their flexibility. This paper proposes an ... -
Adaptive s-aloha cdma as an alternative way of integrating services in mobile environments
(2000-05)
Article
Accés obertCode-division multiple-access (CDMA) schemes appear to be very promising access techniques for coping with the requirements of third-generation mobile systems, mainly because of their flexibility. This paper proposes an ... -
Adaptive schemes for packet data in a ds-cdma environment
(IEEE INSTITUTE OF ELECTRICAL AND ELECTRONICS ENGINEERS, INC., 1997)
Text en actes de congrés
Accés obertThis paper presents a novel adaptive DS-CDMA slotted-ALOHA packet random access scheme for improving the throughput of the conventional DS-CDMA slotted-ALOHA system. For this purpose a mobile-assisted algorithm is envisaged ... -
An efficient data transmission policy in an integrated voice-data ds-cdma network
(IEEE Vehicular Technology Society, 1998)
Text en actes de congrés
Accés obertCDMA schemes appear to be promising access techniques for coping with the requirements of third-generation mobile systems, mainly because of their flexibility. This paper proposes an adaptive S-ALOHA DS-CDMA access scheme ... -
An emulator framework for a new radio resource management for QoS guaranteed services in W-CDMA
(IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 2001-10)
Article
Accés obertIn the context of third-generation (3G) systems a mix of services with different requirements are expected. Consequently, packet scheduling mechanisms for quality of service (QoS) guarantees will play a key role. This paper ... -
Analysis and design of the second order delay-lock loop in a CDMA system
(. VEHICULAR TECHNOLOGY CONFERENCE'92, 1992)
Text en actes de congrés
Accés obertIn code-division multiple access (CDMA) systems a delay-lock loop (DLL) is used to keep a fine alignment between sequences. A simulation program for the second-order DLL has been developed. The program allows an optimum ... -
Analysis and evaluation of decentralized multiaccess Mac for ad-hoc networks
(2003)
Text en actes de congrés
Accés obertIn mobile ad-hoc radio networks, terminals are mobile and heterogeneous, the architecture of the network is continuously changing, communication links are packet oriented and radio resources are scarce. Therefore, ... -
Analysis of a type II hybrid ARQ strategy in a DS-CDMA packet transmission environment
(IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 2003-08)
Article
Accés obertA type II hybrid automatic repeat request scheme is considered as a retransmission strategy in a direct-sequence code-division multiple-access packet mobile radio network. An analysis based on equilibrium point analysis ...
