Processing

Please wait...

Settings

Settings

Goto Application

1. WO1994002996 - IMPROVEMENTS IN OR RELATING TO MOBILE CELLULAR RADIO SYSTEMS

Publication Number WO/1994/002996
Publication Date 03.02.1994
International Application No. PCT/GB1993/001577
International Filing Date 26.07.1993
IPC
H04B 1/713 2011.01
HELECTRICITY
04ELECTRIC COMMUNICATION TECHNIQUE
BTRANSMISSION
1Details of transmission systems, not covered by a single one of groups H04B3/-H04B13/123; Details of transmission systems not characterised by the medium used for transmission
69Spread spectrum techniques
713using frequency hopping
H04B 7/26 2006.01
HELECTRICITY
04ELECTRIC COMMUNICATION TECHNIQUE
BTRANSMISSION
7Radio transmission systems, i.e. using radiation field
24for communication between two or more posts
26at least one of which is mobile
CPC
H04B 1/713
HELECTRICITY
04ELECTRIC COMMUNICATION TECHNIQUE
BTRANSMISSION
1Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
69Spread spectrum techniques
713using frequency hopping
H04B 1/715
HELECTRICITY
04ELECTRIC COMMUNICATION TECHNIQUE
BTRANSMISSION
1Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
69Spread spectrum techniques
713using frequency hopping
715Interference-related aspects
H04B 1/7156
HELECTRICITY
04ELECTRIC COMMUNICATION TECHNIQUE
BTRANSMISSION
1Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
69Spread spectrum techniques
713using frequency hopping
7156Arrangements for sequence synchronisation
H04B 2001/71367
HELECTRICITY
04ELECTRIC COMMUNICATION TECHNIQUE
BTRANSMISSION
1Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
69Spread spectrum techniques
713using frequency hopping
7136Arrangements for generation of hop frequencies, e.g. using a bank of frequency sources, using continuous tuning or using a transform
71367using a transform
H04B 7/2634
HELECTRICITY
04ELECTRIC COMMUNICATION TECHNIQUE
BTRANSMISSION
7Radio transmission systems, i.e. using radiation field
24for communication between two or more posts
26at least one of which is mobile
2628using code-division multiple access [CDMA] or spread spectrum multiple access [SSMA]
2634for channel frequency control
Applicants
  • ROKE MANOR RESEARCH LIMITED [GB]/[GB] (AllExceptUS)
  • HULBERT, Anthony, Peter [GB]/[GB] (UsOnly)
Inventors
  • HULBERT, Anthony, Peter
Agents
  • ALLEN, Derek
Priority Data
9215773.424.07.1992GB
Publication Language English (EN)
Filing Language English (EN)
Designated States
Title
(EN) IMPROVEMENTS IN OR RELATING TO MOBILE CELLULAR RADIO SYSTEMS
(FR) PERFECTIONNEMENTS APPORTES AUX SYSTEMES DE RADIOCOMMUNICATIONS CELLULAIRES
Abstract
(EN)
A frequency hopped cellular mobile radio system, comprising a plurality of base stations each affording a cellular region, or cell, within which communication is facilitated with a plurality of mobile units, each of which mobile units is free to move from cell to cell, the system having in combination the following features: a synchronisation system which serves to bring all mobile units within a cell into synchronisation, as observed from the base station of that cell, whereby orthogonal frequency hopping between mobile units of the cell is facilitated, frequency hopping between mobile units in different cells being non-orthogonal; an affiliation strategy which tends to constrain each mobile unit to maintain communication with a base station selected in dependence upon received signal strength; mobile unit transmission power control in dependence upon received signal/noise ratio at a base station, whereby transmitted mobile power tends towards the minimum necessary for acceptable communication; a frequency hopping strategy, wherein the number of bits per hop is limited to a few bits per hop, the actual number of hops being chosen having regard to performance and overall framing delay constraints; Nyquist filtering of signals effective to constrain interference between hops both in the time domain and in the frequency domain, hopped dwells being arranged to extend in time beyond a nominal bit transmission period (before and after the period) so as to overlap; differential phase shift keying (DPSK) modulation combined with randomised quadrature phase shift keyed (QPSK) modulation to decorrelate interference between cells; and, a system of error control coding.
(FR)
Système de radiocommunications cellulaire à sauts de fréquence. Il comporte une pluralité de stations de base dont chacune présente une zone cellulaire ou cellule, dans laquelle les communications sont facilitées par une pluralité d'unités mobiles dont chacun est libre de se déplacer de cellule en cellule. Ledit système associe les unes aux autres les caractéristiques suivantes: un système de synchronisation de toutes les unités mobiles dans une cellule, telle qu'elle est vue depuis la station de base de la cellule en question, afin de faciliter les sauts de fréquence orthogonaux entre les unités mobiles de la cellule, les sauts de fréquence entre les unités mobiles des différentes cellules étant non orthogonaux; une stratégie d'affiliation tendant à contraindre chaque unité mobile à rester en communication avec une station de base sélectionnée en fonction de la force du signal reçu; un réglage de la puissance de transmission des unités mobiles en fonction du rapport signal/bruit reçu par une station de base, la puissance transmise par chaque unité mobile ayant tendance à se rapprocher du minimum nécessaire à une communication admissible; une stratégie de sauts de fréquence, dans laquelle le nombre de bits par saut se limite à quelques bits par saut, le nombre réel de sauts étant choisi en fonction des performances et des limitations du retard global de verrouillage de trame; un filtrage Nyquist de signaux permettant de limiter les parasites entre les sauts à la fois dans le domaine temporel et dans le domaine de fréquences, des paliers à sauts étant adaptés pour s'étendre dans le temps au-delà d'une période nominale de transmission de bits (avant et après cette période) afin qu'ils se chevauchent; une modulation par déplacement de phase différentiel (DPSK) associée à une modulation de phase à quatre états (QPSK) aléatoire, afin d'assurer la décorrélation des parasites entre les cellules; et un système de codage pour la protection contre les erreurs.
Also published as
FI941349
NO19941069
Latest bibliographic data on file with the International Bureau