摘要:
In a contactless IC card system, a modulating circuit manufactured in an IC form is operable at a high power efficiency. The demodulating apparatus is configured to include: first signal output means for outputting a first output signal having a predetermined phase with respect to that of an input signal, a second signal output means for outputting a second output signal having a predetermined phase with respect to that of the input signal, gate means for gating at least the second output signal, calculation means for adding, or subtracting the first output signal and the second output signal; and control means for controlling the operation of the gate means in response to a logic level of input data.
摘要:
An IC card, an IC card processor, and an IC card system are simply arranged to perform full-duplex data exchange efficiently using a frequency band in such a manner that a transmission signal sent from the IC card processor is received by an antenna, the transmission signal is demodulated, and a response signal to be sent from the antenna is formed by modulating a main carrier having the same frequency as a main carrier of the transmission signal with a response data sequence in such a manner that a sideband of the response signal does not overlap a sideband of the transmission signal along the frequency axis.
摘要:
Method and apparatus for providing communication with a higher communication rate while maintaining the occupied frequency band narrow, a signal processing unit of a reader/writer unit Biphase Shift Keying (BPSK)-modulates data to be transmitted, and thereafter outputs the modulated signal to a modem. The modem Amplitude Shift Keying (ASK)-modulates the modulated signal and outputs the ASK-modulated signal to a first loop coil. The first loop coil generates a magnetic field corresponding to the modulated wave. An IC card converts a part of the magnetic field radiated from the reader/writer unit with another loop coil to generate a power source from the electrical signal, and also extracts the data transmitted. In the case of transmitting the data to the reader/writer unit, a load of another loop coil is changed in accordance with the data. The reader/writer unit detects, with the first loop coil, any change in load of another loop coil of the IC card magnetically coupled with the first loop coil.
摘要:
A method for a communication device includes determining whether a first radio frequency (RF) signal at a level of at least a first predetermined field threshold is detected. The method also includes generating a second RF signal at a level of at least a second predetermined field threshold greater than the first predetermined field threshold, when the communication device receives an instruction to generate the second RF signal and the determining determines that the first RF signal at the level of at least the first predetermined field threshold is not detected. The method further includes receiving a load modulated RF signal in response to the second RF signal.
摘要:
A method for a communication device includes determining whether a first radio frequency (RF) signal at a level of at least a first predetermined field threshold is detected. The method also includes generating a second RF signal at a level of at least a second predetermined field threshold greater than the first predetermined field threshold, when the communication device receives an instruction to generate the second RF signal and the determining determines that the first RF signal at the level of at least the first predetermined field threshold is not detected. The method further includes receiving a load modulated RF signal in response to the second RF signal.
摘要:
An application program relating to a process of an integrated circuit is stored in a virtual integrated circuit storage area server apparatus. Following a mutual authentication between the IC and the virtual storage area server apparatus through a portable communication function unit, the server apparatus executes the application program. Additionally, through the IC, the portable communication function unit, a wireless communication line, and a network, communicate with an IC_R/W apparatus and perform a process relating to a service in collaboration with each other.
摘要:
In a contactless IC card system, a modulating circuit manufactured in an IC form is operable at a high power efficiency. The demodulating apparatus is configured to include: signal processing means for producing first and second input signals; first clamping circuit for clamping said first input signal; second clamping circuit for clamping said second input signal; first band limiting means for removing a component of said first input signal from an output signal of said first clamping circuit; second band limiting means for removing a component of said second input signal from an output signal of said second clamping circuit; and calculating means for adding, or averaging an output signal of said first band limiting means and an output signal of said second band limiting means.
摘要:
An application program relating to a process of an integrated circuit 21 is stored in a virtual integrated circuit 21 storage area server apparatus 13. Following a mutual authentication between the IC 21 and the virtual IC storage area server apparatus 13 through a portable communication function unit 20, the server apparatus 13 executes the application program. Additionally, through the IC 21, the portable communication function unit 20, a wireless communication line 17, and a network 18, communicate with an IC_R/W apparatus 11 and perform a process relating to a service in collaboration with each other.
摘要:
A data communication device includes a first antenna; a semiconductor circuit for generating signals for use in outputting communication data through the first antenna, the semiconductor circuit having a CMOS configuration of a combination of a P-channel MOS transistor and an N-channel MOS transistor on a single chip; and an antenna connection circuit through which the semiconductor circuits is connected to the first antenna. The semiconductor circuit includes a power-supply-connecting MOS drain output part and a ground-connecting MOS drain output part. The antenna connection circuit has a first electric element for inhibiting a current from flowing into the corresponding semiconductor circuit in the power-supply-connecting MOS drain output part.
摘要:
In a communication terminal that is capable of carrying out communications based on a plurality of communication standards, for example, a cellular phone, information representing a reception carrier frequency of a wireless channel being received by a cellular-phone functional block is output from a CPU to a contactless-IC-card-reader/writer functional block. In the contactless-IC-card-reader/writer functional block, a controller controls a switching circuit to switch a transmission carrier frequency being used so that harmonic components of an electromagnetic wave radiated from a coil antenna will not work as an electromagnetic-interference wave that affects reception sensitivity of the cellular-phone functional block.