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1.发明公开MESSAGE TRANSMISSION SYSTEM, A METHOD OF OPERATING THE MESSAGE TRANSMISSION SYSTEM, AND A PRIMARY STATION THEREFOR 失效新闻传播系统，方法用于操作NEWS传输系统和主站THEREFOR
公开(公告)号：EP0932987A2
公开(公告)日：1999-08-04
申请号：EP98901462.0
申请日：1998-02-16
CPC分类号： H04W84/025 , H04W88/185
摘要： A message transmission system, such as a paging system, in which message compression is practised through the use of identical memories (46, 80 (not shown)) in a primary station (10) and a secondary station (20 - not shown) storing identically the most frequently used n (where n is an integer) items of numeric only or alpha-numeric data. The contents of the memories (46, 80) are updatable dynamically to reflect changes in the most frequently used items by the primary station examining messages to be sent to a particular addressee to see if an item is being used more frequently than one of those stored in which case the primary station at its own volition re-writes the data in the memories (46, 80). The secondary station automatically acknowledges that its memory has been updated. The inventive technique may also be applied to frequently used phrases and also to complex graphical data which it is more efficient to store in the primary and secondary stations and to transmit a memory location indicator.
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公开(公告)号：EP0848847A1
公开(公告)日：1998-06-24
申请号：EP97920915.0
申请日：1997-05-28
CPC分类号： G08B5/228
摘要： A display system comprises a display apparatus such as an electronic notice board (36), TV set (46) or computer monitor. Radio messages are received by a point-to-point receiving apparatus (16), such as a wide area digital pager, adjustably mounted on the display apparatus. The receiving apparatus (16) generates non-electrical signals which are transmitted to the display apparatus, the display apparatus having means (40, 41, 42) enabling the signals to be displayed. The receiving apparatus (16) is adjusted to minimise the reduction in the quality of the radio signal received by said receiving apparatus.
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公开(公告)号：EP0765583A2
公开(公告)日：1997-04-02
申请号：EP95914498.0
申请日：1995-04-24
CPC分类号： H04W88/187 , H04W8/245 , H04W88/022
摘要： A selective call system in which base stations (BS1, BS2) transmit address code words at a predetermined data rate. High rate telescript information having a length of say more than 500 characters, for example an E-mail message, is transmitted at a data rate greater than that used for sending address code words. In the event of the system being a simulcast system, intersymbol interference (ISI) may occur and in order to reduce the effects of ISI on the decoding of the telescript information whilst avoiding an unnecessarily large drain on the secondary station's batteries, the telescript information as received for a specific secondary station is stored and subsequently equalised in non-real time. The mobile terminal unit may include a transmitter for transmitting acknowledgement or other response signals, for example as spread spectrum signals. The acknowledgement signals may be used as a means for locating the mobile terminal unit.
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公开(公告)号：EP0721714A1
公开(公告)日：1996-07-17
申请号：EP95924476.0
申请日：1995-07-20
CPC分类号： H04L1/0057 , H04L1/0045
摘要： A method of, and system for, communicating messages in an environment which is subject to fading, in which data to be transmitted is encoded and formatted, a checksum (CSM) is determined for said encoded and formatted data and in which the checksum (CSM) is added to an address code word (ADD) which is concatenated with the encoded and formatted message code words (M1, M2, M3) to form a message. A receiver is energized for receiving transmissions in its predetermined frame. In response to recognising its address code word the concatenated code words are decoded and stored. As each code word is stored, substantially simultaneously a checksum is computed for the message assembled so far and is compared to the checksum (CSM) in the address code word, if and when they are equal it is concluded that a complete message has been received and further analysis of the stored message is terminated.
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公开(公告)号：EP0686324A1
公开(公告)日：1995-12-13
申请号：EP95901574.0
申请日：1994-12-13
发明人： MOORE, Paul, Anthony
摘要： A radio receiver has a frequency down conversion stage (28) including a first passive filter (50, 51, 52) tuned to a lower frequency. An amplifier (56, 58) functioning as a voltage to current converter (54) comprises a resistor (60) which can be shunted by a second passive filter (70, 71, 74) in response to actuation of symmetrically arranged switching devices (72, 73). When the second passive filter shunts the resistor the overall pass band is raised to a higher frequency. Additionally the amplifier has a lower noise figure when the second passive filter shunts the transconductor.
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公开(公告)号：EP0958659A2
公开(公告)日：1999-11-24
申请号：EP98954673.0
申请日：1998-11-30
发明人： MINNIS, Brian, John , WAGNER, Elmar
CPC分类号： H03C3/0983 , H03C3/0966 , H03C3/406 , H03D7/168 , H03J1/0033 , H04B2001/0491
摘要： A transmitter in which a complex low IF digitised signal is applied in quadrature to a complex phase comparator (32) together with a digitised frequency down-converted version of an analogue signal produced by a transmitter VCO (46). The low IF digitised signal serves as a reference against which the digitised frequency down - converted version of the transmitter VCO (46) is compared. The output of the complex phase comparator (32) is converted to an analogue signal which is applied as a control signal to the transmitter VCO. An analogue embodiment of the transmitter which uses zero - IF signals is also disclosed.
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公开(公告)号：EP0824794A2
公开(公告)日：1998-02-25
申请号：EP97904532.0
申请日：1997-02-27
发明人： HOLVOETH, Knud
CPC分类号： H03G3/3068 , H03G1/0088
摘要： A receiver including an rf amplifier (14) having an input, an output and a gain control input (38), means (34-not shown) for deriving a gain control signal and gain control means (36) responsive to the gain control signal for applying a gain setting signal to said gain control input (38). The gain control means (36) comprises at least 2 parallel arranged bias current means (40, 42, 44), at least one (42 or 44) of said at least 2 bias current means including switching means (SW1 or SW2) responsive to a control voltage varying by a predetermined amount relative to a reference voltage (Vref1 or Vref2) for actuating the switching means (SW1 or SW2) to connect or disconnect the bias current means (42 or 44) to or from the gain control input.
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公开(公告)号：EP0809892A1
公开(公告)日：1997-12-03
申请号：EP96937464.0
申请日：1996-11-25
CPC分类号： H04W84/025 , H04B1/707
摘要： A method of reducing computation in spread spectrum signals in which a spread spectrum signal sent by a transmitting station (SS1) includes a group and an individual identity code. A receiver (10, 12) stores the received signals based on their group codes and analyses the stored signals on a group by group basis. This greatly reduces this computation required when recovering individual messages from a number of simultaneously transmitted spread spectrum signals. Optionally the transmitting station may send the group and individual identity code signals simultaneously as quadrature signals.
摘要翻译： 一种减少扩频信号中的计算的方法，其中发射台（SS1）发送的扩频信号包括一个组和一个单独的识别码。 接收器（10,12）基于它们的组代码存储所接收的信号，并逐组地分析所存储的信号。 这大大减少了从多个同时传输的扩频信号恢复单个消息时所需的计算量。 可选地，发射台可以同时发送群组和个人身份代码信号作为正交信号。
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公开(公告)号：EP0789958A1
公开(公告)日：1997-08-20
申请号：EP96924106.0
申请日：1996-08-02
CPC分类号： H04L7/0062 , H04L7/0337
摘要： A method of, and apparatus for, symbol timing recovery, comprising asynchronously sampling a signal burst at a predetermined plurality of times per symbol period, combining corresponding samples occurring in successive sampling cycle periods, making a soft decision on each combination of samples, and selecting for demodulation a timing offset(i) giving the largest soft decision.
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10.发明公开METHOD AND SYSTEM FOR DATA COMMUNICATION, USING A M-ARY MODULATION SCHEME AND INLEAVING MEANS 失效方法和系统进行数据通信采用M级调制和交错手段
公开(公告)号：EP0737386A1
公开(公告)日：1996-10-16
申请号：EP95932890.0
申请日：1995-10-17
CPC分类号： H04L1/0057 , H03M13/27 , H04L1/0071 , H04L27/00 , H04L27/12
摘要： A method of, and system for, communicating s-bit symbols using an M-ary modulation scheme in which a plurality of code words are arranged as rows of a block which is read-out orthogonally to the rows. In order to increase the dependability of the recovered code words, when the code words are stored or read-out the order of the bits forming some of the s-bit symbols is transformed so that those which would have been least significant bits (LSBs) are most significant bits (MSBs) and vice versa, the MSBs being affected less by noise than the LSBs when transmitted. At the receiver those s-bit symbols which have been transformed are restored to their original order.
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