Source: http://www.google.com/patents/US7454182?dq=6377161
Timestamp: 2017-08-23 22:03:15
Document Index: 357321

Matched Legal Cases: ['art 240', 'art 230', 'art 250', 'art 230', 'art 270', 'art 230']

Patent US7454182 - Attenuator with switch function and mobile telephone terminal device using ... - Google Patents
A high frequency part, which amplifies a high frequency signal outputted from an intermediate frequency part and supplies to an antenna, is equipped with a gain controller with switch function. The gain controller with switch function comprises an attenuator with switch function has a function of switching...http://www.google.com/patents/US7454182?utm_source=gb-gplus-sharePatent US7454182 - Attenuator with switch function and mobile telephone terminal device using the same
Publication number US7454182 B2
Application number US 11/758,528
Also published as CN1520217A, CN100450239C, EP1445857A2, EP1445857A3, US7245895, US20040185814, US20070232252
Publication number 11758528, 758528, US 7454182 B2, US 7454182B2, US-B2-7454182, US7454182 B2, US7454182B2
Inventors Masahiko Inamori, Takashi Yamamoto, Masao Nakayama, Kaname Motoyoshi
Patent Citations (13), Non-Patent Citations (2), Classifications (19), Legal Events (6)
Attenuator with switch function and mobile telephone terminal device using the same
US 7454182 B2
14. A mobile telephone terminal device, characterized in comprising: a baseband part (101), which processes a speech signal and a radio part (201), which receives the speech signal processed by said baseband part (101) and communicates with a base station; said radio part (201) is comprised of a sender part (260) which generates a send signal to said base station and a receiver part (220) which receives the send signal from said base station; said sender part (260) is comprised of an intermediate frequency part (230), which is formed by a modulator (231) which modulates an intermediate frequency signal in accordance with the speech signal which is provided from said baseband part (101), a variable gain intermediate frequency amplifier (232) which controls the gain of said intermediate frequency signal and a mixer (233) which performs mixing for frequency conversion from said intermediate frequency signal into a high frequency signal, and a high frequency part (270) which amplifies said high frequency signal outputted from said intermediate frequency part (230) and supplies to an antenna (300); said high frequency part (270) is comprised of a gain controller with switch function (271), which switches a selected band between two bands outputted from said intermediate frequency part (230) and controls the gain of said high frequency signal in the selected band, and two power amplifiers (242) and (252) which respectively power-amplify two outputs from said gain controller with switch function (271); said gain controller with switch function (271) includes an attenuator with switch function (272) which switches a selected band between two bands outputted from said intermediate frequency-part (230) and controls the gain of said high frequency signal in the selected band, said mobile telephone terminal device being characterized in that said baseband part (101) includes a control part (120); said control part (120) detects signal information about a receive signal received by said receiver part (220) and adds a gain control voltage corresponding to this information to said attenuator with switch function (272) so that an output from either one (242) of said two power amplifiers is taken over by an output from the other one (252) of said two power amplifiers; a target value for the output level of the other one (252) of said two power amplifiers is then set in accordance with the signal information about said receive signal; the output level of the other one (252) of said two power amplifiers is compared with the target value for the output level of the other one (252) of said two power amplifiers; a gain control voltage corresponding to the result of the comparison is added to said attenuator with switch function (272) and said variable gain intermediate frequency amplifier (232), thereby follow-up controlling the gains of said attenuator with switch function (272) and said variable gain intermediate frequency amplifier (232) such that the output level of the other one (252) of said two power amplifiers will become equal to the target value for the output level of the other one (252) of said two power amplifiers, and that said attenuator with switch function (272) is comprised of: a first variable resistor (41) which is inserted in a first signal line (47) which connects a first signal input part (43) for said high frequency signal with a first signal output part (45) and for said high frequency signal; a second variable resistor (42) which is inserted in a second signal line (48) which connects a second signal input part (44) for said high frequency signal with a second signal output part (46) for said high frequency signal; a first and a second reference voltage applying parts (51) and (52) which are connected respectively with said first and said second variable resistors (41) and (42); and a gain control voltage applying part (50) which is connected with each one of said first and said second variable resistors (41) and (42) via a common gain control line (49).
The variable gain intermediate frequency amplifier 232 described above is formed by a bipolar transistor in many instances. The variable gain intermediate frequency amplifier 232 is capable of varying the gain over the range of about 30 dB at the linearity of ±1 dB. In this case, the gain is continuously controlled over the range of about 30 dB, by means of a gain control voltage which changes continuously.
The high frequency part 240 is comprised of a variable gain high frequency amplifier 241 which amplifies, using a variable gain, the band-A high frequency signal outputted from the intermediate frequency part 230, a power amplifier 242 which power-amplifies an output from the variable gain high frequency amplifier 241 and a switch 245 which is for selecting the band A. The variable gain high frequency amplifier 241 described above is capable of varying the gain over the range of about 20 dB at the linearity of ±1 dB. In this case, the gain is continuously controlled over the range of about 20 dB, by means of a gain control voltage which changes continuously.
The variable gain high frequency amplifier 241 is comprised of a preamplifier (intermediate power amplifier) 243 and an attenuator 244 which is cascaded with the preamplifier 243 and varies the gain of the band-A high frequency signal which is supplied to the power amplifier (high power amplifier) 242. The attenuator 244 is equipped with a function of changing the attenuation over the range of about 20 dB at the linearity of ±1 dB.
The high frequency part 250 is comprised of a variable gain high frequency amplifier 251 which amplifies, using a variable gain, the band-B high frequency signal outputted from the intermediate frequency part 230, a power amplifier 252 which power-amplifies an output from the variable gain high frequency amplifier 251 and a switch 255 which is for selecting the band B. The variable gain high frequency amplifier 251 described above is capable of varying the gain over the range of about 20 dB at the linearity of ±1 dB. In this case, the gain is continuously controlled over the range of about 20 dB, by means of a gain control voltage which changes continuously.
The variable gain high frequency amplifier 251 is comprised of a preamplifier (intermediate power amplifier) 253 and an attenuator 254 which is cascaded with the preamplifier 253 and varies the gain of the band-B high frequency signal which is supplied to the power amplifier (high power amplifier) 252. The attenuator 254 is equipped with a function of changing the attenuation over the range of about 20 dB at the linearity of ±1 dB.
The high frequency part 270 is comprised of a gain controller with switch function 271 which switches the selected band for and controls the gain of the high frequency signal outputted from the intermediate frequency part 230, a power amplifier 242 which power-amplifies an output in the band A from the gain controller with switch function 271, and a power amplifier 252 which power-amplifies an output in the band B from the gain controller with switch function 271. The gain controller with switch function 271 is capable of switching the selection of the band A or B and varying the gain over the range of about 20 dB at the linearity of ±1 dB in the selected band. In this case, the band switching/selecting operation is executed in response to a gain control voltage which changes continuously and the gain is continuously controlled over the range of about 20 dB or higher.
The attenuator with switch function 272, as described above, switches the selection of the band A or B and varies the gain over the range of about 20 dB at the linearity of ±1 dB in the selected band. To this end, the attenuator with switch function 272 has a switch isolation value of 20 dB or higher and is equipped with a function of varying the gain over the range of about 20 dB or higher as the attenuation of the attenuators.
Utilizing both gain control at the gain controller with switch function 271 and gain control at the variable gain intermediate frequency amplifier 232, the mobile telephone terminal device described above realizes gain control over the range of 50 dB or higher at the linearity of ±1 dB in the selected band. According to the PDC standard, the input stage of the mixer 233 operates in the 200 MHz band while the output stage of the mixer 233 operates in the 940 or 1441 MHz band. It is +30 dBm (where 0 dBm=1 mW) at the output terminal of the power amplifier 242 or the power amplifier 252, it is +8 dBm at the output terminal of the preamplifier 243 or the preamplifier 253, it is −16 dBm at the output terminal of the attenuator with switch function 272, it is −15 dBm at the output terminal of the mixer 233, and it is −20 dBm at the output terminal of the variable gain intermediate frequency amplifier 232.
VDROP=1×10−6×100×103=0.1 (V)
It is further necessary that the difference ΔV is set to such a value which is not influenced by a variation of the threshold value voltage of each field effective transistor during fabrication, a change caused by a temperature change, etc. Considering that variations of the threshold value voltages of the field effective transistors during fabrication are about ±0.1 V and changes associated with temperature changes are about ±0.1 V, the difference ΔV needs be set to a value which is at least equal to or larger than 0.4 V.
V=15 μA×100 kΩ=1.5 V
At this stage, a leak current of 1 μA flowing through the field effective transistors would give rise to a bias variation of 1 μA×100 kΩ=0.1 V, thereby deviating the gain control characteristics and preventing accurate gain control.
US4466126 May 29, 1980 Aug 14, 1984 Sanyo Electric Co., Ltd. Tuner apparatus
US5303268 Jul 25, 1991 Apr 12, 1994 Kabushiki Kaisha Toshiba Automatic power control apparatus
EP0889584A2 Jul 3, 1998 Jan 7, 1999 Siemens Aktiengesellschaft Circuit for switching and tuning of parallel connected filter branches with different frequency range
JPH0239681A Title not available
JPH11346131A Title not available
1 European Search Report dated Jan. 15, 2008.
U.S. Classification 455/249.1, 327/306, 455/236.1, 327/330, 455/197.2
International Classification H04B7/00, H03G3/30, H04B1/06, H03G1/00, H03H11/24, H04B7/005, H03G3/20, H04M1/74
Cooperative Classification H03G1/0088, H03G3/3036, H03H11/245
European Classification H03G3/30D, H03G1/00B8, H03H11/24A