EP0496498A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Time-division duplex radio transceiver
Assignee: Panasonic Holdings Corp
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Filing: 1992-01-09
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Granted: —
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Expires: 2012-01-09
Abstract
Abstract A time-division duplex radio transceiver is disclosed which can avoid the deterioration of reception sensitivity and interferences in other radio communication equipments of the same kind which may be caused in the conventional transceiver by generation of an interfering signal of a transmission frequency or a frequency in the vicinity thereof in the transceiver even upon reception. In the time-division duplex radio transceiver according to the present invention, in order to generate a carrier frequency signal in the transmission state or an intermediate frequency in a transceiver portion, there are provided an oscillator (18; 54) for making oscillation at a frequency higher than the carrier frequency and the intermediate frequency and frequency dividers (20, 21; 56, 57) for frequency-dividing an output of the oscillator, and the operation of the frequency dividers is stopped in the reception state. Accordingly, while the oscillation of the oscillator is always continued, it is possible to prevent the transmission frequency or the frequency from being generated in the vicinity thereof in the transceiver in the reception state.
Inventors
- 👤 Naoya Morita
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-29 22:56
CPC Classifications
H; H04; H04M; H04M1/00; H04M1/72; H04M1/725; H04M1/72502; H04B; H04B1/00; H04B1/38; H04B1/40; H04B1/54; H04B1/56; H04L; H04L5/00; H04L5/14; H04L5/1469; H04L5/1484; H04L5/1492
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
113 words
A radio transceiver including a transmitter portion for use in a transmission state of said transceiver and a receiver portion for use in a reception state of said transceiver, said transmitter portion emitting a transmission carrier signal of a predetermined frequency in said transmission state, said transceiver comprising: an oscillator (18, 54) which oscillates at a frequency higher than said predetermined frequency of said transmission carrier signal; and first frequency divider means (20, 21, 56, 57) for frequency-dividing an output of said oscillator to generate said transmission carrier signal; wherein an operation of said first frequency divider is stopped so as to prohibit generation of said transmitting carrier signal in said reception state.
Claim 2
Dependent Claim
60 words
A radio transceiver according to Claim 1, further comprising second frequency divider means (22, 23, 58, 59) having a division ratio different from that of said first frequency divider means, wherein switching-over from said first frequency divider means to said second frequency divider means is made so as to prohibit generation of said transmitting carrier signal in said reception state.
Claim 3
Dependent Claim
118 words
A radio transceiver including a transmitter portion for use in a transmission state of said transceiver and a receiver portion for use in a reception state of said transceiver, said transmitter portion providing with an intermediate frequency signal to be mixed with another signal to generate a transmission carrier signal of a predetermined frequency, said transceiver comprising: an oscillator (54) which oscillates at a frequency higher than a frequency of said intermediate frequency signal; and first frequency divider means (56, 57) for frequency-dividing an output of said oscillator to generate said intermediate frequency signal, wherein an operation of said first frequency divider is stopped so as to prohibit generation of said intermediate frequency signal in said reception state.
Claim 4
Dependent Claim
58 words
A radio transceiver according to Claim 3, further comprising second frequency divider means (58, 59) having a division ratio different from that of said first frequency divider means, wherein switching-over from said first frequency divider means to said second frequency divider means is made so as to prohibit generation of said intermediate frequency signal in said reception state.
Claim 5
Dependent Claim
135 words
A radio transceiver according to Claim 2, wherein said receiver portion comprises at least one stage of superheterodyne frequency converter (11, 47), said superheterodyne frequency converter uses a local oscillation signal of a predetermined frequency, and wherein, in order to selectively generate said transmission carrier signal to be emitted in said transmission state and said local oscillation signal supplied to said superheterodyne frequency converter in said reception state, said oscillator (18, 54) oscillates at a frequency higher than each of the frequencies of said transmission carrier signal and local oscillation signal, and said first and second frequency divider means (20, 21, 56, 57 and 22, 23, 58, 59) are switched over to frequency-divide the output of said oscillator with division ratios respectively corresponding to the frequencies of said transmission carrier signal and local oscillation signal.
Claim 6
Dependent Claim
134 words
A radio transceiver according to Claim 4, wherein said receiver portion comprises at least one stage of superheterodyne frequency converter (11, 47), said superheterodyne frequency converter uses a local oscillation signal of a predetermined frequency, and wherein, in order to selectively generate said intermediate frequency signal for use in said transmission state and said local oscillation signal supplied to said superheterodyne frequency converter in said reception state, said oscillator (18, 54) oscillates at a frequency higher than each of the frequencies of said intermediate frequency signal and local oscillation signal, and said first and second frequency divider means (20, 21, 56, 57 and 22, 23, 58, 59) are switched over to frequency-divide the output of said oscillator with division ratios respectively corresponding to the frequencies of said intermediate frequency signal and local oscillation signal.
Claim 7
Dependent Claim
51 words
A radio transceiver according to Claim 3, further comprising a second oscillator (60) for converting said intermediate frequency signal in said transmission portion into said transmission carrier signal, and for converting a reception signal into an intermediate frequency signal of a frequency lower than said reception frequency in said reception portion.
Claim 8
Dependent Claim
140 words
A radio transceiver comprising: signal generating means (18) for generating a signal of a first frequency; first frequency-dividing means (20, 21) for frequency-dividing the first frequency signal into a signal of a second frequency; second frequency-dividing means (22, 23) for frequency-dividing the first frequency signal into a signal of a third frequency; first change-over means (19) for connecting said signal generating means selectively to said first frequency-dividing means and said second frequency-dividing means; modulating means (5) for modulating the second frequency signal by a signal to be transmitted; antenna means (9) for making transmission/reception of a signal; mixing means (11) for mixing a reception signal and the third frequency signal; demodulating means (14) for demodulating an output of said mixing means; and second change-over means (7) for connecting said antenna means selectively to said modulating means and said mixing means.
Claim 9
Dependent Claim
29 words
A radio transceiver according to Claim 8, wherein a division ratio of said first frequency-dividing means (20, 21) is different from that of said second frequency-dividing means (22, 23).
Claim 10
Dependent Claim
29 words
A radio transceiver according to Claim 9, wherein the division ratio of said first frequency-dividing means (20, 21) is larger than that of said second frequency-dividing means (22, 23).
Claim 11
Dependent Claim
95 words
A radio transceiver according to Claim 8, wherein an operation of said first change-over means (19) of connecting said signal generating means (18) to said first frequency-dividing means (20, 21) and an operation of said second change-over means (7) of connecting said antenna means (9) to said modulating means (5) are simultaneously performed, and an operation of said first change-over means of connecting said signal generating means to said second frequency-dividing means (22, 23) and an operation of said second change-over means of connecting said antenna means to said mixing means (11) are simultaneously performed.
Claim 12
Dependent Claim
193 words
A radio transceiver comprising: first signal generating means (54) for generating a signal of a first frequency; second signal generating means (60) for generating a signal of a second frequency; first frequency-dividing means (56, 57) for frequency-dividing the first frequency signal into a signal of a third frequency; second frequency-dividing means (58, 59) for frequency-dividing the first frequency signal into a signal of a fourth frequency; first change-over means (55) for connecting said first signal generating means selectively to said first frequency-dividing means and said second frequency-dividing means; modulating means (35) for modulating the third frequency signal by a signal to be transmitted; first mixing means (38) for an output of said modulating means and the second frequency signal; antenna means (42) for making transmission/reception of a signal; second mixing means (44) for mixing a reception signal and the second frequency signal; second change-over means (40) for connecting said antenna means selectively to said first mixing means and said second mixing means; third mixing means (47) for mixing an output of said second mixing means and the fourth frequency signal; and demodulating means (50) for demodulating an output of said third mixing means.
Claim 13
Dependent Claim
29 words
A radio transceiver according to Claim 12, wherein a division ratio of said first frequency-dividing means (56, 57) is different from that of said second frequency-dividing means (58, 59).
Claim 14
Dependent Claim
29 words
A radio transceiver according to Claim 12, wherein the division ratio of said first frequency-dividing means (56, 57) is larger than that of said second frequency-dividing means (58, 59).
Claim 15
Dependent Claim
17 words
A radio transceiver according to Claim 12, wherein said second frequency is higher than said third frequency.
Claim 16
Dependent Claim
18 words
A radio transceiver according to Claim 12, wherein said second frequency is a frequency in a quasi-microwave band.
Claim 17
Dependent Claim
69 words
A radio transceiver according to Claim 12, wherein said second change-over means (40) connects said antenna means (42) to said first mixing means (38) when said first change-over means (55) connects said first signal generating means (54) to said first frequency-dividing means (56, 57) and to said second mixing means (44) when said first change-over means connects said first signal generating means to said second frequency-dividing means (58, 59).
Claim 18
Dependent Claim
111 words
A transceiver comprising: signal generating means (18) for generating always a signal of a first frequency; first frequency-dividing means (20, 21) for frequency-dividing an output of said signal generating means into a second frequency lower than said first frequency; and second frequency-dividing means (22, 23) for frequency-dividing the output of said signal generating means into a third frequency lower than said first frequency and different from said second frequency, wherein said first and second grequency-dividing means being alternately driven, a signal of said second frequency being used as a transmission carrier signal, and a signal of said third frequency being used as a signal for frequency conversion of a reception signal.
Claim 19
Dependent Claim
188 words
A transceiver comprising: first signal generating means (54) for generating always a signal of a first frequency; first frequency-dividing means (56, 57) for frequency-dividing an output of said first signal generating means into a second frequency lower than said first frequency; second frequency-dividing means (58, 59) for frequency-dividing the output of said first signal generating means into a signal of a second frequency lower than said first frequency and different from said second frequency; and second signal generating means (60) for generating a signal of a fourth frequency higher than said second and third frequencies, wherein said first and second frequency-dividing means being alternately driven, a signal of said second frequency being used as a wave to be modulated by a transmission signal, a signal of said fourth frequency being used as a local oscillation signal for frequency-converting a modulating wave and a local oscillation frequency for converting a reception signal into a first intermediate frequency, and a signal of said third frequency being used as a local oscillation signal by which the reception signal converted into said first intermediate frequency is converted into a second intermediate frequency.
Claim 20
Dependent Claim
137 words
A transceiver comprising: signal generating means (18) for generating always a signal of a first frequency; first frequency-dividing means (20, 21) for frequency-dividing an output of said signal generating means into a signal of a second frequency lower than said first frequency; and second frequency-dividing means (22, 23) for frequency-dividing the output of said signal generating means into a signal of a third frequency lower than said first frequency and different from said second frequency, wherein said first frequency-dividing means being selectively connected to said signal generating means, said second frequency-dividing means being always connected to said signal generating means, a signal of said second frequency being used as a signal to be modulated by a transmission signal, and a signal of said third frequency being used as a signal for frequency conversion of a reception signal.
Claim 21
Dependent Claim
60 words
A transceiver according to Claim 20, further comprising second signal generating means (60) for generating a signal of a fourth frequency higher than said second and third frequencies, the signal of said fourth frequency being used as a local oscillation frequency for frequency-converting a modulating signal and a local oscillation frequency for converting a reception signal into an intermediate frequency.
Claim 22
Dependent Claim
170 words
A transceiver comprising: first signal generating means (71) for generating always a signal of a first frequency; first change-over means (73) for connecting said first signal generating means selectively to first frequency-dividing means (20, 21); second signal generating means (72) for generating always a signal of a second frequency; and second change-over means (74) for connecting said second signal generating means selectively to second frequency-dividing means (22, 23), wherein said second change-over means disconnecting said second signal generating means and said second frequency-dividing means when said first change-over means connects said first signal generating means and said first frequency-dividing means, said first change-over means disconnecting said first signal generating means and said first frequency-dividing means when said second change-over means connects said second signal generating means and said second frequency-dividing means, an output of said first frequency-dividing means being used as a signal to be modulated by a transmission signal, and an output of said second frequency-dividing means being used as a signal for frequency conversion of a reception signal.
Claim 23
Dependent Claim
65 words
A transceiver according to Claim 22, further comprising third signal generating means (60) for generating a signal of a frequency higher than output frequencies from said first and second frequency-dividing means, an output of said third signal generating means being used as a local oscillation wave for frequency-converting a modulating signal and a local oscillation wave for converting the reception signal into an intermediate frequency.
References Cited (Backward Citations)
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