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公开(公告)号：EP0600960A1
公开(公告)日：1994-06-15
申请号：EP92917548.0
申请日：1992-08-19
发明人： MÄKINEN, Jarmo
IPC分类号： H04B1
摘要： L'invention se rapporte à un émetteur-récepteur à modulation de fréquence, dans lequel l'émetteur comprend un oscillateur (1) haute fréquence à modulation de fréquence et le récepteur comprend, monté en cascade, un mélangeur haute fréquence (2) dont le signal d'oscillateur local est un signal de sortie modulé produit par l'oscillateur haute fréquence (1), et un mélangeur à fréquence intermediaire (4) ayant un signal d'oscillateur local à fréquence intermédiaire contenant la modulation de transmission. Selon l'invention, l'émetteur-récepteur comprend de plus un troisième mélangeur (5) destiné à produire le signal d'oscillateur local à fréquence intermédiaire à partir d'un signal de sortie modulé envoyé par l'oscillateur haute fréquence.
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2.发明公开METHOD IN DIGITAL QUADRATURE MODULATOR AND DEMODULATOR, AND DIGITAL QUADRATURE MODULATOR AND DEMODULATOR 失效方式的数字正交调制器和解调器和数字正交调制器和解调器
公开(公告)号：EP0941593A1
公开(公告)日：1999-09-15
申请号：EP97913230.0
申请日：1997-11-28
发明人： MÄKINEN, Jarmo
IPC分类号： H04L27
CPC分类号： H04L27/3863 , H04L27/364 , H04L2027/0016
摘要： The invention relates to a method for measuring imperfections in a digital quadrature modulator and demodulator operation, and to a digital quadrature modulator and quadrature demodulator. The modulator of the invention comprises means (11) for modulating quadrature-phase I and Q input signals to generate an output signal comprising quadrature-phase I and Q components; means (12) for taking momentary amplitude samples from the output signal of the modulator (11) at a rate based on a symbol clock (SCLK) of the modulator; means (13) for classifying a direction angle of the symbol to be modulated at a particular time into a particular direction angle sector; means (13) for linking the amplitude samples of the output signal to the direction angle sector corresponding to the symbol to be transmitted at a particular time; and means (13) for comparing the amplitudes of the samples belonging to each direction angle sector with other direction angle sectors or with an ideal value for determining the imperfections of the output signal of the modulator.
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公开(公告)号：EP0709008A1
公开(公告)日：1996-05-01
申请号：EP94916997.0
申请日：1994-06-02
发明人： MÄKINEN, Jarmo
IPC分类号： H04L27
CPC分类号： H04L27/2332
摘要： The invention relates to a method for demodulating a digitally modulated signal and to a demodulator. According to the method, a signal (S) to be received is mixed essentially to quadrature related I and Q baseband signals. For improving the interference tolerance of the demodulator, for instance, differences (α) between directional angles (β, η) of sequential shifts of a signal point on I/Q plane are measured from the baseband signals and said difference is utilized for decision-making concerning a received symbol.
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4.发明授权
公开(公告)号：EP0497801B1
公开(公告)日：1995-07-19
申请号：EP90915315.7
申请日：1990-10-19
发明人： MÄKINEN, Jarmo
CPC分类号： H03C3/0966 , H03C3/0941 , H03C3/095 , H03D1/2281 , H03L7/087 , H03L7/235
摘要： The invention relates to a phase locked loop for producing a reference carrier for a coherent detector, comprising a first phase detector (9) which compares the estimated carrier frequency of an incoming signal and the frequency of a local reference carrier oscillator (11) and produces a control signal proportional to the phase difference between said two frequencies. The oscillator (11) comprises a reference oscillator (1), a loop oscillator (5), a second phase detecting means (2) having inputs to which the output of the reference oscillator (1) and the output of the loop oscillator (5) are connected; and frequency adjusting means (6) which in response to said control signal adjust the frequency of the reference carrier oscillator (11) by simultaneously adjusting both the reference oscillator (1) and the loop oscillator (5).
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公开(公告)号：EP0698313A1
公开(公告)日：1996-02-28
申请号：EP94915169.0
申请日：1994-05-13
发明人： HÄKKINEN, Hannu , MÄKINEN, Jarmo , TOIVONEN, Mikko
摘要： The invention relates to a method for starting a radio transmitter. In the method a transmission frequency is generated by a phase/frequency-locked loop which comprises a phase/frequency comparator (101), a loop filter (102) and a voltage-controlled oscillator (105), and the start-up is performed by switching on an operating voltage (Ucc) to the voltage-controlled oscillator (105). To minimize the frequency error of the transmitter at the start-up, measuring data about relationship between the control voltage (Vc) of the oscillator and the output frequency (VCOFreq) of the oscillator at a specified calibration temperature are pre-stored in connection with the oscillator, and immediately before switching on the operating voltage (Ucc), control voltage (Vc) needed for locking onto the selected output frequency at the prevailing temperature is estimated and the estimated control voltage is set as the control voltage of the oscillator.
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公开(公告)号：EP0600960B1
公开(公告)日：1995-11-02
申请号：EP92917548.7
申请日：1992-08-19
发明人： MÄKINEN, Jarmo
IPC分类号： H04B1/40
摘要： The invention relates to a frequency-modulated transceiver wherein the transmitter comprises a frequency-modulated high frequency oscillator (1) and the receiver comprises, coupled to a cascade, a high frequency mixer (2) whose local oscillator signal is a modulated output signal from the high frequency oscillator (1), and an intermediate frequency mixer (4) having an intermediate frequency local oscillator signal containing transmission modulation. In accordance with the invention the transceiver further comprises a third mixer (5) for providing said intermediate frequency local oscillator signal from a modulated output signal of the high frequency oscillator.
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公开(公告)号：EP0698313B1
公开(公告)日：1999-04-28
申请号：EP94915169.0
申请日：1994-05-13
发明人： HÄKKINEN, Hannu , MÄKINEN, Jarmo , TOIVONEN, Mikko
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公开(公告)号：EP0720793A1
公开(公告)日：1996-07-10
申请号：EP94927673.0
申请日：1994-09-22
发明人： MÄKINEN, Jarmo
摘要： The invention relates to a digital radio link and radio link system comprising two radio link terminals (A, B) establishing a fixed radio connection between them. In the system, the radio link terminals transmit alternately at the same radio frequency, each one of the radio link terminals (A, B) comprising (a) baseband modulator means (12a; 12b) in the transmitting branch for generating baseband modulation signals from a digital data stream (TXD); (b) demodulator means in the receiving branch for generating a base-band data stream (RXD) by demodulating baseband signals to be received; (c) means (22, 24) for forming an RF transmitting signal directly from said baseband modulation signals and for forming said baseband signals to be received directly from the RF signal to be received; and (d) timing means (16a; 16b) for connecting the radio link terminal alternately to a transmitting and receiving mode. To achieve a link and a link system that are economically advantageous and as simple as possible, the means comprise a single common quadrature mixer (22) and a local oscillator (24) controlling it, the transmitting and receiving branch being separated at the baseband.
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