Abstract: In a two-way communication system made up of a portable communication device and a fixed communication device, the portable communication device includes a stasis/movement determining circuit configured to convert a change in position of the portable communication device into an electric signal, and to determine from the electric signal whether the portable communication device is in a moving state or a stationary state in which the portable communication device does not move for a set length of time. The communication system performs control in which a two-way communication circuit is suspended when the stationary state is detected and the portable communication device is outside the range of communication to and from the fixed communication device, and is activated when the moving state of the portable communication device is detected while the two-way communication circuit is suspended.

Abstract: In a keyless system including a car-mounted device and a portable device carried by a user, the portable device detects the static state of the portable device for an arbitrarily set time period or longer with a static action detection section, and transmits a response signal serving as a response to a challenge signal transmitted from the car-mounted device on condition that the static state has been detected by the static action detection section. This can allow vehicle control such as locking and unlocking of a door of a vehicle through a simple action not requiring operation with a user's hand, and can prevent unnecessary vehicle control not intended by the user.

Abstract: In a two-way communication system made up of a portable communication device and a fixed communication device, the portable communication device includes a stasis/movement determining circuit configured to convert a change in position of the portable communication device into an electric signal, and to determine from the electric signal whether the portable communication device is in a moving state or a stationary state in which the portable communication device does not move for a set length of time. The communication system performs control in which a two-way communication circuit is suspended when the stationary state is detected and the portable communication device is outside the range of communication to and from the fixed communication device, and is activated when the moving state of the portable communication device is detected while the two-way communication circuit is suspended.

Abstract: In a keyless system including a car-mounted device and a portable device carried by a user, the portable device detects the static state of the portable device for an arbitrarily set time period or longer with a static action detection section, and transmits a response signal serving as a response to a challenge signal transmitted from the car-mounted device on condition that the static state has been detected by the static action detection section. This can allow vehicle control such as locking and unlocking of a door of a vehicle through a simple action not requiring operation with a user's hand, and can prevent unnecessary vehicle control not intended by the user.

Abstract: A signal transmission system has a modulation signal converter 1 that generates a modulation signal using a Manchester code with a duty ratio of 50% in accordance with transmission data; a clock generator 6 that generates a clock with the amount of delay with respect to the rising or falling edge of the modulation signal; and a data detector 5 that generates received data by sampling the modulation signal in synchronization with the clock. Since the modulation signal converter 1 generates the modulation signal by combining the Manchester code with the duty ratio of 50%, its duty ratio is always 50% independently of the transmission data, thereby preventing the DC offset of the modulation signal on the receiving side. Accordingly, it offers an advantage of achieving good communication quality with a simple circuit configuration without producing the DC offset in the modulation signal on the receiving side.

Abstract: A first clock generation circuit 21 generates a first clock rising at the time which is delayed by ?T (0.5<?<1.0) from the transition point of each data of a received signal having a time period of T which is Manchester-encoded. A second clock generation circuit 22 generates a second clock rising at the time which is delayed by ?T (0.5<?<1.0) from the transition point, ?T being different from ?T. A data detection circuit 31 outputs first and second detection results of the received signal on the basis of the first and second clocks, and a determination circuit 41 performs determination on the received signal on the basis of the first and second detection results.

Abstract: A signal transmission system has a modulation signal converter 1 that generates a modulation signal using a Manchester code with a duty ratio of 50% in accordance with transmission data; a clock generator 6 that generates a clock with the amount of delay with respect to the rising or falling edge of the modulation signal; and a data detector 5 that generates received data by sampling the modulation signal in synchronization with the clock. Since the modulation signal converter 1 generates the modulation signal by combining the Manchester code with the duty ratio of 50%, its duty ratio is always 50% independently of the transmission data, thereby preventing the DC offset of the modulation signal on the receiving side. Accordingly, it offers an advantage of achieving good communication quality with a simple circuit configuration without producing the DC offset in the modulation signal on the receiving side.

Abstract: A portable communication machine includes RF data generating means, RF wireless transmitting means for transmitting transmission data as an RF signal, RF wireless receiving means for receiving an RF signal transmitted from a vehicle-mounted machine, RF data analyzing means for analyzing received data, key operating means for instructing to control a vehicle by a user, storing means for storing control data of a vehicle-mounted information apparatus, attachable/detachable external apparatus communicating means, and controlling means for controlling the RF data generating means, the RF data analyzing means, the key operating means and the external apparatus communicating means, and is used along with an external apparatus and the vehicle-mounted information apparatus.

Abstract: A remote control system for a car-mounted device capable of realizing communication performance required for a keyless function and communication performance required for a smart function while suppressing increase in circuit scale. The remote control system includes a portable unit and an in-car unit. The portable unit includes: a function judgment mechanism judging whether the keyless function or the smart function is used; an amplification mechanism controlling transmission power in response to a result of judgment obtained at the function judgment mechanism; and a system clock generator controlling a transmission band in response to a result of judgment obtained at the function judgment part. The in-car unit includes: an in-car function judgment mechanism judging whether the keyless function or the smart function is used; and in-car system clock generator controlling a receiving band in response to a result of judgment obtained at the in-car function judgment mechanism.

Abstract: An on-vehicle communication device according to the present invention includes initial signal estimating unit 243b for estimating initial data based on a part of the transmission command signal from the mobile device. Thus, it also includes PN signal generating unit 243c for generating a PN signal based on the initial data estimated by the initial signal estimating unit, and partial correlating unit 243d for calculating a correlation value between the transmission command signal from the mobile device and the PN signal. Thus, it also includes a data demodulating unit 244 for demodulating the transmission command signal from the mobile device, the starting of the data demodulating unit being controlled based on the correlation value calculated by the partial correlating unit 243d.

Abstract: A remote control system for a car-mounted device capable of realizing communication performance required for a keyless function and communication performance required for a smart function while suppressing increase in circuit scale. The remote control system includes a portable unit and an in-car unit. The portable unit includes: a function judgment mechanism judging whether the keyless function or the smart function is used; an amplification mechanism controlling transmission power in response to a result of judgment obtained at the function judgment mechanism; and a system clock generator controlling a transmission band in response to a result of judgment obtained at the function judgment part. The in-car unit includes: an in-car function judgment mechanism judging whether the keyless function or the smart function is used; and in-car system clock generator controlling a receiving band in response to a result of judgment obtained at the in-car function judgment mechanism.

Abstract: An on-vehicle communication device according to the present invention includes initial signal estimating unit 243b for estimating initial data based on a part of the transmission command signal from the mobile device. Thus, it also includes PN signal generating unit 243c for generating a PN signal based on the initial data estimated by the initial signal estimating unit, and partial correlating unit 243d for calculating a correlation value between the transmission command signal from the mobile device and the PN signal. Thus, it also includes a data demodulating unit 244 for demodulating the transmission command signal from the mobile device, the starting of the data demodulating unit being controlled based on the correlation value calculated by the partial correlating unit 243d.

Abstract: A portable communication machine includes RF data generating means, RF wireless transmitting means for transmitting transmission data as an RF signal, RF wireless receiving means for receiving an RF signal transmitted from a vehicle-mounted machine, RF data analyzing means for analyzing received data, key operating means for instructing to control a vehicle by a user, storing means for storing control data of a vehicle-mounted information apparatus, attachable/detachable external apparatus communicating means, and controlling means for controlling the RF data generating means, the RF data analyzing means, the key operating means and the external apparatus communicating means, and is used along with an external apparatus and the vehicle-mounted information apparatus.