초록 ▼

A battery-powered portable radio receiver and a method of operating the battery-powered radio receiver during Standby Mode in order to decrease battery-current drain is provided. In Standby Mode, a receive path of the radio receiver is activated during a data-detection time interval for the detectio

A battery-powered portable radio receiver and a method of operating the battery-powered radio receiver during Standby Mode in order to decrease battery-current drain is provided. In Standby Mode, a receive path of the radio receiver is activated during a data-detection time interval for the detection of data destined for selected receivers, and a preconditioning time interval for performing pre-conditioning functions with respect to the receiver before the data-detection time interval. The method includes: (a) activating the receive path at a predetermined time instant before the start of the data-detection time interval to perform the pro-conditioning functions with respect to the receiver, (b) detecting a predetermined characteristic of the received signal affected by each of the pre-conditioning functions; (c) comparing each of the predetermined characteristics with e threshold; (d) where the predetermined characteristics are within their respective thresholds, deactivating the receive path until the start of the data-detection time interval, and then reactivating the receive path fur the data-detection time interval; and (e) where the predetermined characteristics are outside their respective thresholds, continuing the pre-conditioning functions until the predetermined characteristics are within their respective thresholds, then deactivating the receive path until the start of the data-detection time interval, and then reactivating the receive path for the data-detection time interval.

대표청구항 ▼

A battery-powered portable radio receiver and a method of operating the battery-powered radio receiver during Standby Mode in order to decrease battery-current drain is provided. In Standby Mode, a receive path of the radio receiver is activated during a data-detection time interval for the detectio

A battery-powered portable radio receiver and a method of operating the battery-powered radio receiver during Standby Mode in order to decrease battery-current drain is provided. In Standby Mode, a receive path of the radio receiver is activated during a data-detection time interval for the detection of data destined for selected receivers, and a preconditioning time interval for performing pre-conditioning functions with respect to the receiver before the data-detection time interval. The method includes: (a) activating the receive path at a predetermined time instant before the start of the data-detection time interval to perform the pro-conditioning functions with respect to the receiver, (b) detecting a predetermined characteristic of the received signal affected by each of the pre-conditioning functions; (c) comparing each of the predetermined characteristics with e threshold; (d) where the predetermined characteristics are within their respective thresholds, deactivating the receive path until the start of the data-detection time interval, and then reactivating the receive path fur the data-detection time interval; and (e) where the predetermined characteristics are outside their respective thresholds, continuing the pre-conditioning functions until the predetermined characteristics are within their respective thresholds, then deactivating the receive path until the start of the data-detection time interval, and then reactivating the receive path for the data-detection time interval. g a reverse current through the interconnecting section, a switching element for selectively connecting the forward current means and said reverse current means to said interconnecting section, so as to combine said forward current and said reverse current, respectively, with said RF input signal and to provide an RF output signal of reduced amplitude which is applied to the mixer stage so that the mixer stage is operated in its linear operating range and intermodulation effects are reduced. 2. The communications receiver according to claim 1, wherein the impedance of said interconnecting section is substantially higher than the impedance of said front end stage and said mixer stage, respectively. 3. The communications receiver according to claim 1, wherein the impedance of said interconnecting section is substantially equal to the impedance of said front end stage and said mixer stage, respectively. 4. The communications receiver according to claim 1, comprising a PIN diode as a fast switch. 5. The communications receiver according to claim 1, wherein said intermediate frequency signal is a baseband signal. 6. The communications receiver according to claim 1, wherein said forward current means and said reverse current means are implemented by the same components. 7. A method for reducing intermodulation effects in a communications receiver having a front end stage for receiving a transmitted RF input signal and a mixer stage for mixing said RE input signal with an oscillator signal so as to provide an intermediate frequency signal, wherein said front end stage is connected to said mixer stage by an interconnecting section, said method comprising the steps of: creating a forward current through said interconnecting section by forward current means, creating a reverse current through said interconnecting section by reverse current means, and selectively connecting said forward current means and said reverse current means to said interconnecting section by selector means, so as to reduce the amplitude of the signal, which is applied to the mixer stage, and the mixer stage is operated in its linear operating range.