EP0151014A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Radio transceiver including an antenna switching circuit
Assignee: NEC Corp
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Filing: 1985-01-28
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Granted: —
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Expires: 2005-01-28
Abstract
Abstract ® A radio transceiver includes an antenna (17), a transmitter (3), a receiver (4), an antenna switching circuit (2a) for selectively connecting the transmitter (3) and the receiver (4) to the antenna (17), a filter (1) connected to the antenna (17) and a series connected first diode (22) and an inductor (23) connected between the end of the fitter (1) and a point of fixed potential, the junction between the first diode (22) and the inductor (23) being connected to an input of the receiver (4), and a second diode (21) being connected between the other end of the filter (1) and an output of the transmitter (3).
Inventors
- 👤 Shigeo Yoshihara
- 👤 Hideo Miyashita
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-24 02:57
CPC Classifications
H; H04; H04B; H04B1/00; H04B1/38; H04B1/40; H04B1/44; H04B1/48
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
147 words
A radio transceiver including an antenna (17), a transmitter (3), a receiver (4), an antenna switching circuit for selectively connecting the transmitter (3) and the receiver (4) to the antenna (17) in response to a transmit/ receive control signal, the antenna switching circuit including a first diode (22) and an inductor (23) connected in series, and a second diode (21), and a filter (1) connected to the antenna (17) and the antenna switching circuit, characterised in that the series connected first diode (22) and the inductor(23)are connected between the end of the filter (1) connected to the antenna (17) and a point of fixed potential, the junction between the first diode (22) and the inductor (23) is connected to an input of the receiver (4), and the second diode (21) is connected between the other end of the filter (1) and an output of the transmitter (3).
Claim 2
Dependent Claim
147 words
A radio transceiver including an antenna (17), a transmitter (3), a receiver (4), an antenna switching circuit for selectively connecting the transmitter (3) and the receiver (4) to the antenna (17) in response to a transmit/ receive control signal, the antenna switching circuit including a first diode (22) and an inductor (23) connected in series, and a second diode (21), and a filter (1) connected to the antenna (17) and the antenna switching circuit, characterised in that the series connected first diode (22) and the inductor(23)are connected between the end of the filter (1) connected to the antenna (17) and a point of fixed potential, the junction between the first diode (22) and the inductor (23) is connected to an input of the receiver (4), and the second diode (21) is connected between the other end of the filter (1) and an output of the transmitter (3).
Claim 3
Dependent Claim
19 words
A radio transceiver as claimed in claim 1, characterised in that the filter (1) is a low pass filter.
Claim 4
Dependent Claim
78 words
A radio transceiver as claimed in either claim 1 or claim 2, characterised in that it includes an impedance circuit (26)(27) at each of the opposite ends of the second diode (21), the value of the impedance circuit (26)(27) becoming high during a receive mode of operation with respect to the antenna side in combination with the filter (1) and providing a resonance circuit for a transmission signal from the transmitter (3) during a transmit mode of operation.
References Cited (Backward Citations)
No citation records indexed.
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