Some content of this application is unavailable at the moment.
If this situation persists, please contact us atFeedback&Contact
1. (WO1997015980) TRANSMITTER COMPRISING CARRIER SUPPRESSION AND DC OFFSET REDUCTION MEANS
Latest bibliographic data on file with the International Bureau

Pub. No.: WO/1997/015980 International Application No.: PCT/IB1996/001132
Publication Date: 01.05.1997 International Filing Date: 22.10.1996
IPC:
H03C 1/06 (2006.01) ,H03C 1/52 (2006.01) ,H03C 3/40 (2006.01) ,H04B 1/30 (2006.01) ,H04B 1/40 (2006.01)
H ELECTRICITY
03
BASIC ELECTRONIC CIRCUITRY
C
MODULATION
1
Amplitude modulation
02
Details
06
Modifications of modulator to reduce distortion, e.g. by feedback, and clearly applicable to more than one type of modulator
H ELECTRICITY
03
BASIC ELECTRONIC CIRCUITRY
C
MODULATION
1
Amplitude modulation
52
Modulators in which carrier or one sideband is wholly or partially suppressed
H ELECTRICITY
03
BASIC ELECTRONIC CIRCUITRY
C
MODULATION
3
Angle modulation
38
by converting amplitude modulation to angle modulation
40
using two signal paths the outputs of which have a predetermined phase difference and at least one output being amplitude-modulated
H ELECTRICITY
04
ELECTRIC COMMUNICATION TECHNIQUE
B
TRANSMISSION
1
Details 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
06
Receivers
16
Circuits
30
for homodyne or synchrodyne receivers
H ELECTRICITY
04
ELECTRIC COMMUNICATION TECHNIQUE
B
TRANSMISSION
1
Details 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
38
Transceivers, i.e. devices in which transmitter and receiver form a structural unit and in which at least one part is used for functions of transmitting and receiving
40
Circuits
Applicants:
PHILIPS ELECTRONICS N.V. [NL/NL]; Groenewoudseweg 1 NL-5621 BA Eindhoven, NL
PHILIPS NORDEN AB [SE/SE]; Kottbygatan 7, Kista S-164 85 Stockholm, SE (SE)
Inventors:
WILSON, John, F.; GB
Agent:
MOODY, Colin, J.; Internationaal Octrooibureau B.V. P.O. Box 220 NL-5600 AE Eindhoven, NL
Priority Data:
9521769.124.10.1995GB
Title (EN) TRANSMITTER COMPRISING CARRIER SUPPRESSION AND DC OFFSET REDUCTION MEANS
(FR) EMETTEUR A SUPPRESSION DE PORTEUSES ET REDUCTION DU DECALAGE DU NIVEAU CONTINU
Abstract:
(EN) A transmitter comprising at least first and second phase related signal paths (I, Q), having respective frequency up-converting means (28, 30, 32, 34), means (35) for combining the output of the respective frequency up-converting means and for supplying the combined signal to power amplifying means (36, 38). A feedback loop is provided which has a coupler (54) for deriving a portion of the power amplifier output signal and supplying it to first and second phase related feedback paths. Each of the feedback paths comprises frequency down-converting means (56, 58, 60). Means (42 to 52) are provided for measuring the dc offsets at the respective inputs of the frequency up-converting means (28, 30) when the feedback around the linearisation loop is reduced to zero without altering the dc offsets produced at the outputs of the frequency down-converting means (56, 58, 60). Subtracting means (20, 22, 68, 70) subtract the measured dc offsets from the feedback loop error signals.
(FR) Emetteur comprenant au moins un premier et un deuxième parcours de signal associé aux phases (I, Q), comportant des multiplicateurs de fréquence (28, 30, 32, 34), et un système pour combiner la sortie des multiplicateurs de fréquence et amener le signal associé à un amplificateur de puissance (36, 38). Une boucle de rétroaction comporte un coupleur (54) permettant de dériver une partie du signal de sortie de l'amplificateur de puissance pour l'amener aux boucles de rétroaction associées à la première et à la deuxième phase. Chaque boucle comprend un diviseur de fréquence (56, 58, 60). Des systèmes (42 à 52) permettent de mesurer les décalages du niveau continu aux entrées correspondantes des multiplicateurs de fréquence (28, 30) quand la rétroaction au niveau de la boucle de linéarisation s'annule, sans altérer les décalages de niveau produits aux sorties des diviseurs de fréquence (56, 58, 60). Des soustracteurs (20, 22, 68, 70) soustraient les décalages de niveau continus mesurés des signaux d'erreur des boucles de rétroaction.
Designated States: JP
European Patent Office (AT, BE, CH, DE, DK, ES, FI, FR, GB, GR, IE, IT, LU, MC, NL, PT, SE)
Publication Language: English (EN)
Filing Language: English (EN)
Also published as:
EP0803147JPH10512133