Apparatus and method for incoming call detection and alarm circuitry for cellular telephones
First Claim
1. An apparatus, monitoring both the electrical power demands made by operation of a wireless network access device on an electrical power source, and the RF transmissions from a device transmitter, for indicating an incoming call to a user, comprising:
- power monitoring means operatively coupled to the electrical power source for providing a power source state signal representative of the current being drawn by operation of the device from the power source;
means, operative upon receipt of said power source state signal, for generating a power source voltage state signal having a value representative of the current being drawn by operation of the device from the power source;
device status determination means for receiving and monitoring said power source voltage state signal and for generating a waiting for call state signal whenever the value of said power source voltage state signal decreases from a first selected higher value to a first selected lower value for a first preselected period of time;
RF monitoring means for detecting RF transmissions by the device transmitter, and for generating a transmitter active status signal whenever RF transmission by the device transmitter is detected for a second preselected period of time;
incoming call detection means for receiving said waiting for call state signal and monitoring said transmitter active status signal, and for generating an alarm start signal whenever said waiting for a call state signal and said transmitter active status signals are both present.
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Accused Products
Abstract
An apparatus and method for indicating an incoming call that generates a voltage signal with a value representative of the current drawn by operation of the device. A circuit monitors the voltage signal and generates a waiting for call state signal whenever the value of the voltage signal decreases from a first selected higher value to a first selected lower value for a first preselected period of time. An RF detection circuit monitors the status of the device'"'"'s transmitter and generates a transmitter active status signal whenever RF appears for a selected period of time. An incoming call detection circuit generates an alarm start signal whenever the waiting for call state and transmitter active status signals are present and either the voltage signal increases from a second selected lower value to a second selected higher value and remains at or above the second selected higher value for a second preselected period of time, or the current goes from a lower preselected current value to a higher preselected current value and remains at or above the higher current value for a third preselected period of time. An alarm, operative upon receipt of the alarm start signal, indicates an incoming call to a user. A circuit monitors the battery voltage and disables the apparatus whenever the battery voltage drops below a preselected cutoff value to avoid damage to the battery.
35 Citations
29 Claims
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1. An apparatus, monitoring both the electrical power demands made by operation of a wireless network access device on an electrical power source, and the RF transmissions from a device transmitter, for indicating an incoming call to a user, comprising:
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power monitoring means operatively coupled to the electrical power source for providing a power source state signal representative of the current being drawn by operation of the device from the power source; means, operative upon receipt of said power source state signal, for generating a power source voltage state signal having a value representative of the current being drawn by operation of the device from the power source; device status determination means for receiving and monitoring said power source voltage state signal and for generating a waiting for call state signal whenever the value of said power source voltage state signal decreases from a first selected higher value to a first selected lower value for a first preselected period of time; RF monitoring means for detecting RF transmissions by the device transmitter, and for generating a transmitter active status signal whenever RF transmission by the device transmitter is detected for a second preselected period of time; incoming call detection means for receiving said waiting for call state signal and monitoring said transmitter active status signal, and for generating an alarm start signal whenever said waiting for a call state signal and said transmitter active status signals are both present. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
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12. An apparatus, monitoring both the electrical power demands made by operation of a wireless network access device on an electrical power source, and the RF transmissions from a device transmitter, for indicating an incoming call to a user comprising:
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power monitoring means operatively coupled to the electrical power source for providing a power source state signal representative of the current being drawn by operation of the device from the power source; means, operative upon receipt of said power source state signal, for generating a power source voltage state signal having a value representative of the current being drawn by operation of the device from the power source; device status determination means for receiving and monitoring said power source voltage state signal and for generating a waiting for call state signal whenever the value of said power source voltage state signal decreases from a first selected higher value to a first selected lower value for a first preselected period of time; RF monitoring means for detecting RF transmissions by the device transmitter, and for generating a transmitter active status signal whenever RF transmission by the device transmitter is detected for a second preselected period of time; incoming call detection means for receiving said waiting for call state signal and said transmitter active status signal, and monitoring said power source voltage state signal, and for generating an alarm start signal whenever said waiting for call state signal is present and, (1) said power source voltage state signal increases from a second selected lower value to a second selected higher value and remains at or above said second selected higher value for a second preselected period of time, or, (2) said transmitter active status signal is present. - View Dependent Claims (13, 14, 15, 16, 17, 18, 19, 20, 21, 22)
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23. An method for monitoring the electrical power demands made by operation of a wireless network access device on a source of electrical power, and the RF transmissions from a device transmitter, for indicating an incoming call to a user comprising:
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monitoring the electrical current being drawn by operation of the device from the power source and generating a power source state signal representative of the current being drawn by operation of the device; receiving said power source state signal and generating, based thereon, a power source voltage state signal having a value representative of the current being drawn by operation of the device from the power source; generating a waiting for call state signal whenever the value of said power source voltage state signal decreases from a first selected higher value to a first selected lower value for a first preselected period of time; monitoring the RF transmissions by the device transmitter, and generating a transmitter active status signal whenever RF transmission by the device transmitter is detected for a preselected period of time; generating an alarm start signal whenever said waiting for call state signal and said transmitter active signal are both present. - View Dependent Claims (24, 25, 26, 27, 28, 29)
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Specification