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1. 发明授权

US5241694A Circuit for forming low power levels in a transmitter of a radio telephone 失效
标题翻译：用于在无线电话机的发射机中形成低功率电平的电路
公开(公告)号：US5241694A
公开(公告)日：1993-08-31
申请号：US512783
申请日：1990-04-20
申请人： Risto Vais/anen , Jukka Sarasmo , Vesa Pekkarinen
发明人： Risto Vais/anen , Jukka Sarasmo , Vesa Pekkarinen
IPC分类号： H03G3/20 , H04B1/04
CPC分类号： H03G3/3042 , H04B2001/0416
摘要： The present invention concerns a circuit for forming low power levels in a transmitter of a radio telephone. By a power amplifier (1) of the transmitter is formed the maximum power level and a plurality of lower power levels. As taught by the invention, very low power levels can be produced by controling the power of the RF signal leaking through the power amplifier (1) when said signal is not amplified by the power amplifier. For controlling the leakage power, a PIN diode attenuator (4) connected before the power amplifier (1) is used.

2. 发明授权

US5118965A Analog pulse converter from square to triangular to cos.sup.2 wave 失效
标题翻译：模拟脉冲转换器从平方到三角形到COS2波
公开(公告)号：US5118965A
公开(公告)日：1992-06-02
申请号：US490159
申请日：1990-03-07
申请人： Risto Vaisanen , Jukka Sarasmo , Vesa Pekkarinen
发明人： Risto Vaisanen , Jukka Sarasmo , Vesa Pekkarinen
IPC分类号： G06G7/22 , H03K4/94 , H03K6/04
CPC分类号： H03K4/94 , G06G7/22 , H03K6/04
摘要： The invention relates to the forming of a control pulse for the transmitter in a GSM radio telephone system. A cos.sup.2 pulse is formed by means of an analog circuit from a rectangular pulse which is first shaped into a triangular pulse which may be somewhat clipped at its peak. The triangular pulse is further shaped into a cos.sup.2 pulse. The circuit also includes the selection of the abruptness of the triangular pulse and, thereby, the abruptness of the cos.sup.2 pulse.

3. 发明授权

US5214372A Linearizing circuit for dectection of a RF-power sensor 失效
标题翻译：线性化电路用于检测RF功率传感器
公开(公告)号：US5214372A
公开(公告)日：1993-05-25
申请号：US777453
申请日：1991-10-11
申请人： Risto Vaisanen , Jukka Sarasmo , Vesa Pekkarinen
发明人： Risto Vaisanen , Jukka Sarasmo , Vesa Pekkarinen
IPC分类号： G01R21/01
CPC分类号： G01R21/01
摘要： The present invention concerns a circuit processes the power signal emitted from an RF power sensor (SK) of a radio telephone to create a detector voltage which is proportional to the power level of the radio telephone transmitter. The circuit comprises a transistor (Q2) acting as an active rectifier, which in the ascending part of the positive half cycle of the power signal charges a capacitor (C3). During the descending part of the power signal the capacitor starts to discharge with a time constant which is remarkably greater than the cycle length of the power signal. The transistor is biassed by means of a transistor (Q1) so that it is conductive even at the lowest power levels.
摘要翻译：本发明涉及电路处理从无线电话的RF功率传感器（SK）发射的功率信号，以产生与无线电话发射机的功率电平成正比的检测器电压。电路包括用作有源整流器的晶体管（Q2），其在功率信号的正半周期的上升部分对电容器（C3）充电。在功率信号的下降部分期间，电容器开始放电，时间常数明显大于功率信号的周期长度。晶体管通过晶体管（Q1）偏置，使得即使在最低功率电平下它也是导电的。

4. 发明授权

US5152004A Procedure for forming low power levels in a radio telephone transmitter 失效
标题翻译：在无线电电话发射机中形成低功率电平的步骤
公开(公告)号：US5152004A
公开(公告)日：1992-09-29
申请号：US516762
申请日：1990-04-30
申请人： Risto Vaisanen , Jukka Sarasmo , Vesa Pekkarinen
发明人： Risto Vaisanen , Jukka Sarasmo , Vesa Pekkarinen
IPC分类号： H03G3/20 , H04B1/04
CPC分类号： H03G3/3042 , H03F2203/7239 , H04B2001/0416
摘要： A circuit for forming low power levels in a radio telephone transmitter in which high power levels are produced in a controllable amplifier stage (1), for instance in a class-C power amplifier. According to the procedure, a RF signal is before the amplifier stage (1) divided into two branches in a power divider (4), in one of which the Rf signal is conducted to said amplifier stage (1) for forming high power levels, and in the other branch the RF signal is conducted to an element (5) by which low power levels are produced, and said branches are combined in the output (RFout) of the transmitter. The element (5) may be a PIN diode attenuator.

5. 发明授权

US5311179A Method for amending the effect of offset voltage variations from the output voltage in a D/A converter 失效
标题翻译：修正D / A转换器中偏移电压变化与输出电压的影响的方法
公开(公告)号：US5311179A
公开(公告)日：1994-05-10
申请号：US970281
申请日：1992-10-30
申请人： Risto Vaisanen , Jukka Sarasmo
发明人： Risto Vaisanen , Jukka Sarasmo
IPC分类号： H03G3/20 , H03M1/06 , H03M1/10 , H03M1/66
CPC分类号： H03G3/3047 , H03M1/0607 , H03M1/66
摘要： The present invention relates to an offset voltage zeroing method of a D/A converter, with the aid of which oscillations of the output voltage of said D/A converter can be radically reduced. An output signal of the converter is carried to a first terminal of a capacitor (5). A second terminal of the capacitor is coupled to a reference voltage (V.sub.ref) with a controllable switch (6) as long as there are no pulses in the output of the converter. As a result, an amended output signal is obtained from the second terminal.
摘要翻译：本发明涉及一种D / A转换器的偏移电压归零方法，借此可以大大降低所述D / A转换器的输出电压的振荡。转换器的输出信号被传送到电容器（5）的第一端子。只要转换器的输出中没有脉冲，电容器的第二端子与可控开关（6）耦合到参考电压（Vref）。结果，从第二终端获得修正的输出信号。

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