Communication system, communication method, and data processing apparatus

• US 20050077356A1
• Filed: 10/28/2003
• Published: 04/14/2005
• Est. Priority Date: 12/17/2002
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Morita, Tadashi, Fujii, Kunihide, Kusakabe, Susumu, Takayama, Yoshihisa, Tsurumi, Kazushige
• Granted Patent: US 7,346,061 B2
• Time in Patent Office: Days
• US Class Current: 235/451
• CPC Class Codes: G06K 19/0723 the record carrier comprising an arrangement for non-contact communication, e.g. wireless communication circuits on transponder cards, non-contact smart cards or RFIDs
• CPC Class Codes: G06K 7/10237 the reader and the record carrier being capable of selectively switching between reader and record carrier appearance, e.g. in near field communication [NFC] devices where the NFC device may function as an RFID reader or as an RFID tag
• CPC Class Codes: H04B 5/0031 for data transfer
• CPC Class Codes: H04B 5/0056 for use in interrogation, identification or read/write systems record carriers G06K7/00, G06K19/00; for railways B61L3/12
• CPC Class Codes: H04B 5/0075 using inductive coupling transformers or inductances adapted for inductive coupling H01F38/14
• CPC Class Codes: H04B 5/24 Inductive coupling
• CPC Class Codes: H04B 5/72 for local intradevice communication
• CPC Class Codes: H04B 5/77 for interrogation
• CPC Class Codes: H04L 27/02 Amplitude-modulated carrier systems, e.g. using on-off keying; Single sideband or vestigial sideband modulation H04L27/32 takes precedence
• CPC Class Codes: H04N 21/25808 Management of client data terminal profiles in network data switching protocols H04L67/303
• CPC Class Codes: H04W 4/02 Services making use of location information
• CPC Class Codes: H04W 4/80 Services using short range communication, e.g. near-field communication [NFC], radio-frequency identification [RFID] or low energy communication
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals

Abstract

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.

Claims

1. A communication system of performing, wireless communication using a carrier having a single frequency, comprising:

first and second data processing apparatuses, each comprising;

a modulator configured to modulate the carrier into a data signal to be transmitted at one of a plurality of transfer rates wherein, a transfer rate used between the first and second data processing apparatuses is changeable in one transaction,

the first and second data processing apparatuses are configured to communicate using an active mode in which data is transmitted by outputting a carrier, and

the first and second data processing apparatuses are configured to communicate using a passive mode in which one of the first and second data processing apparatuses transmits data by outputting a carrier, while the other data processing apparatus transmits data by performing load modulation on the carrier output by said one of the first and second data processing apparatuses; and

the first and second data processing apparatuses are configured to transmit data using any communication mode of the active mode and the passive mode, the communication mode being maintained during at least one transaction.

2. The communication system according to claim 1, wherein:

the first and second data processing apparatuses each comprise an encoder configured to encode data into a Manchester code; and

said modulator obtains a data signal transmitted at at least one transfer rate among the transfer rates by performing amplitude modulation on the carrier in accordance with the Manchester code.

3. The communication system according to claim 1, wherein:

one of the first and second data processing apparatuses is configured to acquire information corresponding to a plurality of transfer rates which are usable by the other data processing apparatus, and the transfer rate for use between the first and second data processing apparatuses in one transaction is changed based on the information.

4. The communication system according to claim 3, wherein:

one of the first and second data processing apparatuses is configured to acquire information corresponding to all the transfer rates which are usable by the other data processing apparatus by transmitting a command and receiving a response to the command.

5. A communication method of performing, by a first data processing apparatus and at least one second data processing apparatus, wireless induction communication using a carrier having a single frequency, said communication method comprising the steps of:

selecting, by said first data processing apparatus, a target apparatus as a communication party from among said at least one second data processing apparatus;

determining a transfer rate for use in data transmission by the first and second data processing apparatuses from a plurality of transfer rates;

changing a communication parameter concerning the communication between said first data processing apparatus and said target apparatus;

transmitting a command to request data exchange by said first data processing apparatus and transmitting a response to the command by said target apparatus, and exchanging data between said first data processing apparatus and said target apparatus; and

releasing the second data processing apparatus, which is selected as said target apparatus;

selecting one of an active and a passive communication mode for use in data transmission by said first data processing apparatus and said target apparatus, in said active mode said first data processing apparatus and said target apparatus output carriers for transmitting data and in said passive mode said first data processing apparatus outputs a carrier and said target apparatus performs load modulation on the carrier output by said first data processing apparatus for transmitting data.

6. The communication method according to claim 5, wherein:

said first data processing apparatus and said target apparatus each are configured to obtain a data signal to be transmitted at at least one transfer rate among a plurality of transfer rates by encoding the data into a Manchester code and performing amplitude modulation in accordance with the Manchester code.

7. The communication method according to claim 5, wherein:

said first data processing apparatus is configured to acquire information relating to a plurality of transfer rates usable by said target apparatus, and changes, based on the information, a transfer rate for use in one transaction between said first data processing apparatus and said target apparatus.

8. A communication method according to claim 7, wherein:

said first data processing apparatus is configured to acquire information relating to all transfer rates usable by said target apparatus by transmitting a command to the target requesting available transfer rates and receiving a response from the target to the command.

9. A data processing apparatus for performing electromagnetic communication using a carrier having a single frequency, comprising:

an electromagnetic wave generator configured to form an RF (Radio Frequency) field by generating electromagnetic waves;

a modulator configured to transmit data at a predetermined transfer rate by modulating the carrier corresponding to the electromagnetic waves, in accordance with the data; and

a demodulator configured to demodulate data transmitted at a predetermined transfer rate by demodulating the electromagnetic waves generated by another apparatus, wherein

said modulator transmits the data at a plurality of transfer rates; and

said data communication apparatus is configured to recognize a communication party based on a response sent back for transmission of the data at each of the transfer rates, and a transfer rate for use in data transmission between said data processing apparatus and said communication party is determined among the plurality of transfer rates.

10. A data processing apparatus for performing wireless communication using a carrier having a single frequency, comprising:

a modulator configured to transmit data at a predetermined rate by modulating the carrier corresponding to electromagnetic waves, in accordance with the data; and

a demodulator configured to acquire data transmitted at a predetermined transfer rate by demodulating electromagnetic waves, wherein

said modulator transmits data to a communication party by transmitting, to the communication party, a response to a command which is acquired by said demodulating means after being transmitted from the communication party;

said demodulator performs demodulation at one of a plurality of transfer rates; and

one of the plurality of transfer rates capable of being demodulated by said demodulator is determined as a transfer rate for use in data transmission to the communication party.

11. The data processing apparatus according to claim 10, wherein:

said modulator performs load modulation on the carrier corresponding to electromagnetic waves generated by said communication party.

12. The data processing apparatus according to claim 10, further comprising:

an electromagnetic wave generator configured to generate an RF (Radio Frequency) field by generating electromagnetic waves, wherein

said modulator modulates the carrier corresponding to electromagnetic waves generated by said electromagnetic wave generator.

13. A method of commencing near-field wireless communications between an initiator device and a target device, comprising the steps of:

detecting, by the initiator, a presence of a radio frequency (RF) field;

transmitting a first electromagnetic wave to the target, the electromagnetic wave configured to carry a request at a first transmission rate selected from a plurality of transmission rates when an RF field is not detected within a time period defined by T_IDT+n×

T_RFW, where T_IDT is an initial delay time, n is a random number, and T_RFW is an RF waiting time to start one of either an active and a passive mode of communication; and

initiating communication between the initiator and the target in one of the active mode and the passive mode of communication, wherein

when in the active communication mode, the target performs the steps of

detecting a presence of a radio frequency (RF) field,

transmitting a response to the initiator by transmitting a second electromagnetic wave from the target when the RF field is not detected in said detecting step within a time period defined by T_ADT+n×

T_RFW, where T_ADT is an active delay time, n is a random number, and T_IDT>

T_ADT, wherein

when in the passive communication mode, the target performs the step of

sending a response to the initiator energized from the first electromagnetic wave received from the initiator, said sending step including performing load modulation.

14. The communication method as claimed in claim 13, wherein, when the active mode of communication has been initiated between the target and the initiator,

generating the RF field at the initiator to send a command to the target after receiving the response and after a lapse of the active delay time, said command requesting a change from the first transmission rate to a second transmission rate.

15. A method for near field wireless communications between an initiator data communications device and a target communications device at a specified carrier frequency, comprising the steps of:

detecting, by the initiator, a presence of a radio frequency (RF) field;

generating an RF field at the initiator when the RF field is not detected within a time period defined by T_IDT+n×

T_RFW, where T_IDT is an initial delay time, n is a random number, and T_RFW is a delay time before initiating an active or passive communication mode between the initiator and the target;

transmitting, from the initiator to the target, a request for operational attributes relating to the target via the RF field at one of a plurality of predetermined transfer rates;

activating another RF field at the target when the RF field is not detected within a time period defined by T_ADT+n×

T_RFW, where T_ADT is an active delay time, n is a random number, and T_IDT>

T_ADT;

transmitting a response to the request for operational attributes received from the initiator at the one of the plurality of predetermined transfer rates; and

transmitting, from the initiator, one of a request to modify at least one of the operational attributes relating to the target and a message initiating data communications between the target and the initiator at the one of the predetermined transfer rates.

16. A method for near field wireless communications between an initiator data communications device and a target communications device at a specified carrier frequency, comprising the steps of:

detecting, by the initiator, a presence of a radio frequency (RF) field;

generating an RF field at the initiator when the RF field is not detected within a time period defined by T_IDT+n×

T_RFW, where T_IDT is an initial delay time, n is a random number, and T_RFW is a delay time before initiating an active or passive communication mode between the initiator and the target;

transmitting, from the initiator to the target, a request for operational attributes relating to the target via the RF field at one of a plurality of predetermined transfer rates;

generating an RF field at the target by performing load modulation on the RF field received from the initiator;

transmitting a response to the request for operational attributes received from the initiator at the one of the plurality of predetermined transfer rates; and

transmitting, from the initiator, one of a request to modify at least one of the operational attributes relating to the target and a message initiating data communications between the target and the initiator at the one of the predetermined transfer rates.

17. A system for near field wireless communications between a plurality of data communications devices at a specified carrier frequency, comprising:

an initiator data communications device, including

a modulator configured to modulate the carrier into a data signal to be transmitted at one of a plurality of predetermined transfer rates;

a detector configured to detect a presence of a radio frequency (RF) field within a time period defined by T_IDT+n×

T_RFW, where T_IDT is an initial delay time, n is a random number, and T_RFW is a delay time before initiating an active or passive communication mode between the initiator and the target; and

a transmitter configured to generate an RF field at the initiator when an RF field is not detected and transmit a request for operational attributes relating to the target via the RF field at one of a predetermined transfer rates;

said system for near-field wireless communications further comprising a target data communications device, the target device including

a detector configured to detect a presence of a radio frequency (RF) field within a time period defined by T_ADT+n×

T_RFW, where T_ADT is an active delay time, n is a random number, and T_IDT>

T_ADT;

a modulator configured to modulate the carrier into a data signal to be transmitted at one of a plurality of predetermined transfer rates to the initiator; and

a transmitter configured to generate an RF field at the initiator when an RF field is not detected and transmit a response to the request for operational attributes to the initiator via the RF field at one of a predetermined transfer rates.

18. A system for near field wireless communications between a plurality of data communications devices at a specified carrier frequency, comprising:

an initiator data communications device, including

a modulator configured to modulate the carrier into a data signal to be transmitted at one of a plurality of predetermined transfer rates;

a detector configured to detect a presence of a radio frequency (RF) field within a time period defined by T_IDT+n×

T_RFW, where T_IDT is an initial delay time, n is a random number, and T_RFW is a delay time before initiating an active or passive communication mode between the initiator and the target; and

a transmitter configured to generate an RF field at the initiator when an RF field is not detected and transmit a request for operational attributes relating to the target via the RF field at one of a predetermined transfer rates;

said system for near-field wireless communications further comprising a target data communications device, the target device including

a modulator configured to modulate the carrier into a data signal to be transmitted at one of a plurality of predetermined transfer rates to the initiator; and

a transmitter configured to generate an RF field at the target by performing load modulation on the RF field received from the initiator and transmit a response to the request for operational attributes to the initiator via the RF field at one of a predetermined transfer rates.

19. A system for near field wireless communications between a plurality of data communications devices at a specified carrier frequency, comprising:

an initiator data communications device, including

a modulator configured to modulate the carrier into a data signal to be transmitted at one of a plurality of predetermined transfer rates;

a detector configured to detect a presence of a radio frequency (RF) field within a time period defined by T_IDT+n×

T_RFW, where T_IDT is an initial delay time, n is a random number, and T_RFW is a delay time before initiating an active or passive communication mode between the initiator and the target; and

a transmitter configured to generate an RF field at the initiator when an RF field is not detected and transmit a request for operational attributes relating to the target via the RF field at one of a predetermined transfer rates;

said system for near-field wireless communications further comprising a target data communications device, the target device including

a detector configured to detect a presence of a radio frequency (RF) field within a time period defined by T_ADT+n×

T_RFW, where T_IDT is an active delay time, n is a random number, and T_IDT>

T_ADT;

a modulator configured to modulate the carrier into a data signal to be transmitted at one of a plurality of predetermined transfer rates to the initiator; and

a transmitter configured to generate an RF field at the initiator when an RF field is not detected and transmit a response to the request for operational attributes to the initiator via the RF field at one of a predetermined transfer rates, and further configured to generate an RF field at the target by performing load modulation on he RF field received from the initiator and transmit a response to the request for operational attributes to the initiator via the RF field at one of a predetermined transfer rates.

20. A method of performing near-field wireless communications between an initiator data communication device and a target wireless communication device, comprising the steps of:

detecting, by the initiator, the presence of a radio frequency (RF) field;

generating an RF field at the initiator when the RF field is not detected within a time period defined by T_IDT+n×

T_RFW, where T_IDT is an initial delay time, n is a random number, and T_RFW is a delay time before initiating an active or passive communication mode between the initiator and the target; and

transmitting, from the initiator to the target, a request for operational attributes relating to the target via the RF field at one of a plurality of predetermined transfer rates.

21. The method of claim 20, further comprising the steps of:

generating an RF field at the target when an RF field is not detected within a time period defined by T_ADT+n×

T_RFW, where T_ADT is an active delay time, n is a random number, and T_IDT>

T_ADT;

transmitting a response to the request for operational attributes received from the initiator at the one of the plurality of predetermined transfer rates; and

transmitting, from the initiator, one of a request to modify at least one of the operational attributes relating to the target and a message initiating data communications between the target and the initiator at the one of the predetermined transfer rates.

22. The method of claim 20, further comprising the steps of:

sending a response to the initiator from the target which is energized from the first electromagnetic wave received from the initiator, the response being sent by load modulation.

23. A system for near field wireless communications between a plurality of data communications devices at a specified carrier frequency, comprising:

an initiator data communications device, comprising;

a modulator configured to modulate the carrier into a data signal to be transmitted at one of a plurality of predetermined transfer rates;

a detector configured to detect the presence of a radio frequency (RF) field within a time period defined by T_IDT+n×

T_RFW, where T_IDT is an initial delay time, n is a random number, and T_RFW is a delay time before initiating an active or passive communication mode between the initiator and the target; and

a transmitter configured to generate an RF field at the initiator when an RF field is not detected and transmit a request for operational attributes relating to the target via the RF field at one of a predetermined transfer rates.

24. The system of claim 23, further comprising:

a target data communications device, the target device comprising;

a detector configured to detect a presence of a radio frequency (RF) field within a time period defined by T_ADT+n×

T_RFW, where T_ADT is an active delay time, n is a random number, and T_IDT>

T_ADT;

a modulator configured to modulate the carrier into a data signal to be transmitted at one of a plurality of predetermined transfer rates to the initiator; and

a transmitter configured to generate an RF field at the initiator when an RF field is not detected and transmit a response to the request for operational attributes to the initiator via the RF field at one of a predetermined transfer rates.

25. The system of claim 23, further comprising:

a target data communications device, the target device comprising;

a modulator configured to modulate the carrier into a data signal to be transmitted at one of a plurality of predetermined transfer rates to the initiator; and

a transmitter configured to generate an RF field at the target by performing load modulation on the RF field received from the initiator and transmit a response to the request for operational attributes to the initiator via the RF field at one of a predetermined transfer rates.

26. A communication apparatus for performing near-field wireless communication using a carrier having a single frequency, comprising:

a detector configured to detect a presence of an external radio frequency (RF) field within a predetermined time period;

a transmitter configured to generate a RF field by generating electromagnetic waves;

a modulator configured to transmit data at a predetermined transfer rate by modulating the carrier corresponding to the electromagnetic waves in accordance with the data;

a demodulator configured to demodulate data transmitted at a predetermined transfer rate by demodulating the electromagnetic waves generated by another communication apparatus; and

the communication apparatus configured to recognize a communication party based on a data transmitted from the another communication apparatus at the predetermined transfer rate, and the communication apparatus is further configured to exchange data with the another communications apparatus relating to the functional capabilities of each of the communication apparatus and the another communication apparatus.

27. A communication apparatus for near-field wireless communications at a specified carrier frequency configured to operate in an active and passive communication mode, comprising:

a transmitter configured to generate a RF field by generating electromagnetic waves;

a modulator configured to transmit data at a predetermined transfer rate by modulating the carrier corresponding to the electromagnetic waves in accordance with the data;

a detector configured to detect a presence of a radio frequency (RF) field within a predetermined time period, wherein

when the communication apparatus initiates an active or passive communication mode with another communication apparatus

the detector is configured to detect a presence of a radio frequency (RF) field within a time period defined by T_IDT+n×

T_RFW, where T_IDT is an initial delay time, n is a random number, and T_RFW is a delay time before initiating the communication between the communication apparatus and another communication apparatus; and

the transmitter is configured to generate an RF field at the communication device when an RF field is not detected and transmit a request for operational attributes relating to the another communication apparatus via the RF field at one of a predetermined transfer rates, and

when the communication apparatus responds to a request for initiation of an active communication mode by another communication device

the detector is configured to detect a presence of a radio frequency (RF) field within a time period defined by T_ADT+n×

T_RFW, where T_ADT is an active delay time, n is a random number, and T_IDT>

T_ADT;

the modulator is configured to modulate the carrier into a data signal to be transmitted at one of a plurality of predetermined transfer rates to another communication device; and

the transmitter is configured to generate an RF field at the communication apparatus when an RF field is not detected and transmit a response to the request for operational attributes to the another communication apparatus via the RF field at one of a predetermined transfer rates, and

when the communication apparatus receives a request for initiation of a passive communication mode from another communication device

the transmitter is configured to transmit a response to the request for operational attributes to the initiator at one of a predetermined transfer rates by performing load modulation on the RF field received from the another communication device.