摘要:
A communication system and communication method enable various types of near field communication. NFC communication apparatuses have two features in that each can perform communication in two communication modes and that each can perform data transmission at a plurality of transfer rates. The two communication modes consist of a passive mode and an active mode. In the passive mode, between the NFC communication apparatuses, for example, a first NFC communication apparatus transmits data to a second NFC communication apparatus by modulating electromagnetic waves generated by itself, while the second NFC communication apparatus transmits data to the first NFC communication apparatus by performing load modulation on the electromagnetic waves generated by the first NFC communication apparatus. Alternatively, in the active mode, either of the NFC communication apparatuses transmits data by modulating electromagnetic waves generated by itself. The present innovation can be applied to, for example, an IC card system, etc.
摘要:
A communication apparatus includes a short-range communication unit that receives an inquiry signal from a short-range external communication apparatus and transmits a response signal in response to the inquiry signal. The communication apparatus also includes a long-range communication unit that communicates in a range wider than a communication area of the short-range communication unit. Further, the communication apparatus includes a session key generation unit that generates a session key, and an encrypting unit that encrypts the session key. The communication apparatus uses an encryption key transmitted from an external communication apparatus to encrypt the session key into an encrypted session key, transmits the encrypted session key to the external communication apparatus, and receives from the external communication apparatus a request signal to request a long-range communication, with the session key, by the long-range communication unit by using the short-range communication unit.
摘要:
The present invention relates to a communication system and communication method which enable various types of near field communication, and a data processing apparatus. NFC communication apparatuses 1 to 3 have two features in that each can perform communication in two communication modes and that each can perform data transmission at a plurality of transfer rates. The two communication modes consist of a passive mode and an active mode. In the passive mode, between the NFC communication apparatuses 1 and 2, for example, the NFC communication apparatus 1 transmits data to the NFC communication apparatus 2 by modulating electromagnetic waves generated by itself, while the NFC communication apparatus 2 transmits data to the NFC communication apparatus 1 by performing load modulation on the electromagnetic waves generated by the NFC communication apparatus 1. Alternatively, in the active mode, either of the NFC communication apparatuses 1 and 2 transmits data by modulating electromagnetic waves generated by itself. The present invention can be applied to, for example, an IC card system, etc.
摘要:
The present invention relates to a communication system, a communication device, a communication method, and a program, which make it possible to achieve a reduction in communication time. When performing communication in passive mode, the initiator transmits a polling request frame where a first value is set in time slot information, and when performing communication in simple mode, the initiator transmits a polling request frame where a second value different from the first value is set in time slot information. When the time slot information included in the polling request frame from the initiator has the first value, the target transmits a polling response frame including an ID for identifying the target at the timing of a time slot determined by a random number, and when the time slot information has the second value, the target transmits a polling response frame including real data at the timing of a time slot set in advance. The present invention can be applied to, for example, an IC card system that performs near field communication.
摘要:
A coherent optical receiver includes a 90-degree optical hybrid circuit to which a received signal light is input, I-channel and Q-channel photo detectors to which the outputs of the hybrid circuit are input, a clock extraction circuit which reproduces a clock whose speed is the same as a demodulated signal obtained by demodulating the received signal light and which is synchronized therewith, I-channel and Q-channel sampling circuits which sample the signal outputs from the I-channel and Q-channel photo detectors by use of the clock, and a digital signal processing section which digitally processes the sampled signals, converts them to a digital signal, and outputs the digital signal. The digital signal processing section feeds a phase offset signal detected there back to the clock extraction circuit to thereby control the phase of the clock, and compensates dispersion of light within a fiber and phase fluctuation during free-space propagation.