公开(公告)号：EP1012970A1

公开(公告)日：2000-06-28

申请号：EP99929516.5

申请日：1999-07-07

申请人： Pace Micro Technology Ltd

发明人： COE, Peter W.

IPC分类号： H03J7/02

CPC分类号： H03J7/02

摘要： The invention to which this application relates is to provide a means for use in electrical and electronic apparatus, such as apparatus for the receipt of television signals in either analogue or digital form, and to allow components within the apparatus which are required to operate at set frequencies or within set frequency range, to be set and/or adjusted prior to, or during, use of the apparatus with reference to an RFTV modulator. This ensures that the components are set and maintained within predetermined parameters and also overcomes the need for additional time in the manual setting and/or adjusting of the devices and/or the provision of additional components to prevent frequency drift as is the case in conventional apparatus.

公开(公告)号：EP0972353A1

公开(公告)日：2000-01-19

申请号：EP99901611.6

申请日：1999-01-25

申请人： Nokia Networks Oy

发明人： NIEMELÄ, Kari

IPC分类号： H04B1/40

CPC分类号： H03J7/02 ,  H04B1/40 ,  H04B17/0085 ,  H04B17/309

摘要： The invention relates to a tuning method used in a base station which comprises, in addition to at least one transceiver unit generating signals, a filtering means (30) which is separate from the transceiver unit and filters signals which are generated on the transmitting end of the transceiver unit, of which signals part advances to the filtering means (30) and part is reflected back, and which filtering means is tuned to operate in a predetermined frequency band. The transceiver unit comprises a test signal generating means (140) which generates a control signal and a test signal that is located in a predetermined frequency band, which test signal is transmitted further to the filtering means (30), a means (160) which generates signals of the same magnitude as the signal which advances to the filtering means (30) and is reflected from the filtering means, which signals are connected from the transmitting end to the receiving end of the transceiver. The transceiver unit further comprises a measuring instrument (90) which measures the power of the signals which are connected to the receiving end and estimates the return loss of the filtering means (30) on the basis of the powers measured, an adjustment means (20) which receives the control signal from the generating means (140). The adjustment means (20) tunes the filtering means (30) on thebasis of the control signal it has received if a return loss value obtained as an estimation result is greater than the predetermined limit value of the return loss.

公开(公告)号：EP0904635A1

公开(公告)日：1999-03-31

申请号：EP97927612.0

申请日：1997-05-05

申请人： International Business Machines Corporation ,  Dingsor, Andrew D.

发明人： DINGSOR, Andrew, D.

IPC分类号： H03J7 ,  H04B1 ,  H04L27

CPC分类号： H04L27/142 ,  H03J7/02 ,  H04B1/40 ,  H04L27/12

摘要： A method, apparatus and article of manufacture for compensating for carrier frequency error is disclosed. An FM signal is received from an antenna and the received FM signal is provided to a receiver. The receiver takes the FM signal at the carrier frequency and outputs a baseband signal. This baseband signal is then processed by a DSP which provides carrier frequency compensation and decoding to produce a data stream that a microprocessor provides to a host device. Frequency differences between the FM carrier frequency and the frequency used to demodulate the FM signal can shift the DC bias level of the baseband signal. The DSP compensates for such frequency difference by using a receive compensation value and applying it to each received signal sample. When transmitting, data to be transmitted is provided from the host device to the DSP via a microprocessor. The DSP provides encoding and carrier frequency compensation of the data to provide a baseband signal to a transmitter that modulates the baseband signal to produce anFM signal at a desired carrier frequency. Frequency differences between the desired FM carrier frequency and the frequency used to modulate the baseband signal can produce errors in receiver systems. The DSP compensates for such a frequency difference by using a transmit compensation value and applying it to each encoded signal sample.

公开(公告)号：EP0599414A3

公开(公告)日：1995-11-08

申请号：EP93203239.4

申请日：1993-11-18

申请人： Philips Electronics N.V.

发明人： Mohindra, Rishi, c/o INT. OCTROOIBUREAU B.V.

IPC分类号： H04B1/30 ,  H03J7/02

CPC分类号： H04B1/30 ,  H03D3/007 ,  H03D7/165 ,  H03J7/02

摘要： In known direct conversion receivers, e.g. for paging, for getting a correct polarity a.f.c. signal, the a.f.c. signal is derived from a series arrangement of a phase shifting arrangement and a multiplication arrangement, coupled to quadrature related signals (I, Q). At an output of the series arrangement a bipolar control signal is achieved having a relatively low frequency ripple component giving rise to a relatively slow a.f.c. loop response. The direct conversion receiver (1) according to the present invention comprises a.f.c. means with an offset frequency detector (17) for determining a signal (dct) as the a.f.c. signal (ct), of which an average value is proportional to a frequency offset (δf) of a local oscillator with respect to an rf input signal, the frequency detector (17) having such series arrangement in both I- and Q-paths (4, 5), allowing for a fast a.f.c. loop response, therewith improving the a.f.c performance. Due to the unipolar control signal, a series of positive or negative pulses, depending on the sign of the frequency ofset, less demand is imposed upon signal averaging, i.e. upon the loop filter. Furthermore, the receiver (1) comprises out-of-range detection means (19, 42, 45, 47) for detecting whether a local oscillator frequency (f L ) is outside a predetermined range with respect to a carrier frequency (f C ).

公开(公告)号：EP0674387A1

公开(公告)日：1995-09-27

申请号：EP95301842.1

申请日：1995-03-20

申请人： Samsung Electronics Co., Ltd.

发明人： Choi, Yang-Seok

IPC分类号： H03J7/02

CPC分类号： H03J7/02

摘要： An automatic frequency control apparatus includes a sampling portion (30) for sampling the signal transmitted according to a phase-shift keying method, a phase difference detector (32) for detecting the phase difference between the currently sampled signal (R k ) and the immediately preceding sampled signal (R k-1 ) , and a determinator (34, 36) for determining a reference phase which is the closest to the phase of the transmitted signal using a quantization characteristic of phase during transmission. The frequency offset generated by the distance between the frequency of a carrier wave and the local oscillation frequency of a receiver, or by the Doppler shift, in a MPSK communication method is determined as the phase difference between the detected phase difference information and the determined reference phase information. Since the frequency offset is detected using the signal sampled at the symbol rate, the cost of hardware constituting the apparatus can be reduced. The apparatus can be used for the automatic frequency control of a modem using all types of MPSK modulation.

摘要翻译： 一种自动频率控制装置，包括：采样部分（30），用于对根据相移键控方法发射的信号进行采样;相位差检测器（32），用于检测当前采样信号（Rk） 采样信号（Rk-1）和确定器（34,36），用于使用发送期间的相位的量化特性来确定最接近发射信号的相位的参考相位。 由MPSK通信方法中的载波频率与接收机本地振荡频率之间的距离或多普勒频移产生的频偏被确定为所检测的相位差信息与确定的参考值之间的相位差 相位信息。 由于使用以符号速率采样的信号来检测频率偏移，所以可以减少构成装置的硬件成本。 该装置可用于使用所有类型的MPSK调制的调制解调器的自动频率控制。

公开(公告)号：EP0651520A2

公开(公告)日：1995-05-03

申请号：EP94307720.6

申请日：1994-10-20

申请人： PLESSEY SEMICONDUCTORS LIMITED

发明人： Fobbester, Ian Godfrey

IPC分类号： H03D3/00 ,  H04B1/12 ,  H04Q7/00

CPC分类号： H04L25/065 ,  H03J7/02 ,  H03J7/04 ,  H04B1/26 ,  H04L7/046 ,  H04L27/142 ,  H04L27/148 ,  H04L27/1525

摘要： In a frequency modulated digital radio transmission system, frequency differences between transmitter and receiver which give rise to DC offsets at the output of the demodulator are countered for any one data transmission by establishing a frequency controlling or DC level controlling signal during a preamble sequence having a known constant DC component, such as the sequence 10101 ------- used for clock or data synchronisation, and retaining that controlling signal substantially unaltered for use during the remainder of that data transmission.

摘要翻译： 在频率调制的数字无线电传输系统中，通过在具有频率调制数字无线电传输系统的前导码序列期间建立频率控制或DC电平控制信号来对通过解调器的输出端产生DC偏移的发射机和接收机之间的频率差异进行抵消， 已知的恒定DC分量，例如用于时钟或数据同步的序列10101 - ，并且在该数据传输的剩余时间期间保持该控制信号基本上不改变以供使用。

公开(公告)号：EP0412207B1

公开(公告)日：1994-07-20

申请号：EP89122976.7

申请日：1989-12-13

申请人： MITSUBISHI DENKI KABUSHIKI KAISHA

发明人： Andoh, Akira c/o Mitsubishi Denki Kabushiki Kaisha

IPC分类号： H03J7/02

CPC分类号： H03L7/14 ,  H03J7/02 ,  H03J7/065

公开(公告)号：EP0592975A3

公开(公告)日：1994-07-13

申请号：EP93116403.2

申请日：1993-10-10

申请人： SELECO S.p.A.

发明人： Liverotti, Giorgio

IPC分类号： H04N5/50 ,  H03J1/00

CPC分类号： H03J1/0033 ,  H03J7/02 ,  H04N5/50

摘要： The present invention relates to a tuning method for voltage synthesis television signal receivers; the main characteristic of the invention consists in that a plurality of digital codes, each identifying respectively a voltage corresponding to a television channel, are memorised before the sale of the receiver in a tuning memory (15) of the non volatile digital type, to a corresponding plurality of addresses and that for executing the direct call of the desired channel the user types on a command unit (16) the channel number, that said command unit (16) sends to a control unit (14) of the receiver a corresponding signal and that the control unit (14) reads in the memory (15) the corresponding digital code and sends it to the tuning unit (10) that provides for tuning the desired channel.

公开(公告)号：EP0495514A2

公开(公告)日：1992-07-22

申请号：EP92100751.4

申请日：1992-01-17

申请人： MURATA MANUFACTURING CO., LTD.

发明人： Ishikawa, Youhei ,  Wada, Hidekazu ,  Yamashita, Sadao ,  Kubo, Hiroyuki

IPC分类号： H03J7/02

CPC分类号： H03J7/02

摘要： An auto-tuned apparatus for a band-pass filter (30), wherein, the generated reference signals having a frequency to be set are mixed in a mixer (60) with the output of the band-pass filter (30). These reference signals are also input to the band-pass filter. The direct current component of the output signal of mixer (60) are filtered in a low pass filter (61) and via A/D converter applied to the controll circuit (50).
This control circuit (50) controls via a motor driver (32) the motor (33) for tuning the band pass filter (30) in such a way that the center frequencies of the band-pass filter (30) agrees with the frequency of the reference signal in accordance with the said direct current component. The center frequency of the band-pass filter (30) can thus be adjusted automatically to the desired set value using a simple circuit construction and with a better precision than in the conventional embodiment.

摘要翻译： 一种用于带通滤波器的自动调谐装置，其中，当将参考信号已经被输入到带通滤波器时，具有要设置的给定频率的所生成的参考信号与从带通滤波器输出的信号混合 滤波器，以便将它们相乘以输出相乘结果的信号，对要输出的相乘结果的信号中的直流分量的信号进行滤波，并且控制带通滤波器，使得 带通滤波器可以根据要输出的直流分量的信号与参考信号的频率一致，由此带通滤波器的中心频率可以通过简单的电路结构自动调整到期望的设定值 并且精度优于常规实施例。

公开(公告)号：EP0357876A2

公开(公告)日：1990-03-14

申请号：EP89108922.9

申请日：1989-05-18

申请人： TELEFUNKEN Sendertechnik GmbH

发明人： Jebe, Hans, Dipl.-Ing. ,  Weber, Klaus, Dipl.-Ing.

IPC分类号： H03J7/02

CPC分类号： H03J7/02

摘要： Die Erfindung betrifft ein Verfahren zur Optimierung der Abstimmung eines mit einstellbaren Abstimmitteln (10-16) versehenen Senders auf eine gewünschte Betriebsfrequenz, bei welchem Verfahren zunächst die Einstellung der Abstimmittel (10-16) inner­halb eines Variationsbereichs durch Änderung der Einstell­parameter variiert wird und während dieser Variation gleichzeitig der Wirkungsgrad und/oder die Verlustleistung des Senders bestimmt und zusammen mit den zugehörigen Einstellparametern abgespeichert wird sowie anschließend von diesen gespeicherten Einstellungen diejenige Ein­stellung, für die der höchste Wirkungsgrad bestimmt wurde, als Betriebseinstellung für den Betrieb des Senders auf der gewünschten Betriebsfrequenz ausgewählt und vorgenommen wird.

摘要翻译： 本发明，在该方法中，首先，调谐装置的调整的范围的变化的内变化，通过改变调整参数涉及一种方法，用于优化设置有可调节的调谐装置的发射器的调谐，以期望的操作频率和 这种变化中，在同一时间，效率和/或所述发射器的功率消耗期间确定性开采并与相关联的调整参数，并随后存储在一起，从合成存储的调整，为其中最高效率已经结束开采的调整，是 选择并实现作为发送器的外科手术所需的操作频率操作设置。