TRANSMISSION SYSTEM, TRANSMITTER, RECEIVER, AND TRANSMISSION METHOD

• US 20080304580A1
• Filed: 06/08/2007
• Published: 12/11/2008
• Est. Priority Date: 06/08/2007
• Status: Active Grant

• Current Assignee: Advantest Corporation
• Original Assignee: Advantest Corporation
• Inventors: ICHIYAMA, KIYOTAKA
• Granted Patent: US 7,844,020 B2
• Time in Patent Office: Days
• US Class Current: 375/259
• CPC Class Codes: H04L 25/4904 using self-synchronising codes, e.g. split-phase codes
• CPC Class Codes: H04L 25/4925 using balanced bipolar ternary codes

Abstract

There is provided a transmission system in which a data sequence is transmitted. The transmission system includes a transmitter that generates a transmission signal by converting pieces of data included in the data sequence into data waveforms each of which has (i) a level signal whose signal level is determined by a value of a corresponding one of the pieces of data and (ii) a timing edge indicating a timing to obtain the level signal, and transmits the generated transmission signal, and a receiver that detects the signal level of each of the data waveforms of the received transmission signal at the timing designated by the timing edge of the each data waveform, and outputs a data value corresponding to the detected signal level.

Claims

1. A transmission system in which a data sequence is transmitted, comprising:

a transmitter that generates a transmission signal by converting pieces of data included in the data sequence into data waveforms each of which has (i) a level signal whose signal level is determined by a value of a corresponding one of the pieces of data and (ii) a timing edge indicating a timing to obtain the level signal, and transmits the generated transmission signal; and

a receiver that detects the signal level of each of the data waveforms of the received transmission signal at the timing designated by the timing edge of the each data waveform, and outputs a data value corresponding to the detected signal level.

2. The transmission system as set forth in claim 1, wherein

the transmitter generates the transmission signal by converting the pieces of data included in the data sequence into a pulse waveform including a plurality of pulses each of which varies from a reference level to the signal level at the timing edge and then goes back to the reference level from the signal level, and transmits the generated transmission signal, and

the receiver detects the signal level of each of the plurality of pulses of the received transmission signal at the timing designated by the timing edge of the each pulse, and outputs the data value corresponding to the detected signal level.

3. The transmission system as set forth in claim 2, wherein

the receiver includes

a clock generating section that generates a reception clock based on the timing edge of the each pulse, and

the receiver detects the signal level of the each pulse at a timing designated by the reception clock, and outputs the data value corresponding to the detected signal level.

4. The transmission system as set forth in claim 2, wherein

the receiver further includes

a plurality of level comparators that are provided in association with a plurality of data value candidates one of which is selected to each of the pieces of data included in the data sequence, each of the plurality of level comparators outputting a detection signal when the signal level is equal to or higher than a threshold value determined in accordance with an associated data value candidate, and

the receiver detects the signal level of the each pulse at a timing designated by the detection signal associated with a smallest data value candidate among the plurality of data value candidates, and outputs the data value corresponding to the detected signal level.

5. The transmission system as set forth in claim 2, wherein

the transmitter converts pieces of binary data included in the data sequence into pulses each of which has a polarity determined by a value of a corresponding one of the pieces of binary data, and transmits the pulses, and

the receiver detects the signal level of each of the received pulses at the timing designated by the timing edge of the each pulse, and outputs the data value corresponding to the detected signal level.

6. The transmission system as set forth in claim 5, wherein

the receiver includes:

a positive pulse detecting section that detects a positive pulse from the received transmission signal, the positive pulse having the signal level on a positive side;

a negative pulse detecting section that detects a negative pulse from the received transmission signal, the negative pulse having the signal level on a negative side; and

a clock generating section that generates a reception clock based on the timing edge of the positive pulse detected by the positive pulse detecting section and the timing edge of the negative pulse detected by the negative pulse detecting section.

7. The transmission system as set forth in claim 6, including:

a frequency divider that obtains a frequency-divided signal by dividing, into half, a frequency of one of the positive pulse and the negative pulse, and outputs the obtained frequency-divided signal;

a signal obtaining section that obtains the frequency-divided signal at a timing designated by the reception clock; and

a data regenerating section that regenerates the data sequence based on the frequency-divided signal obtained by the signal obtaining section.

8. The transmission system as set forth in claim 7, wherein

the frequency divider obtains the frequency-divided signal by dividing the frequency of the positive pulse into half, and outputs the obtained frequency-divided signal, and

the data regenerating section obtains a logical XOR between a logical value of the frequency-divided signal for a current cycle and a logical value of the frequency-divided signal for an immediately previous cycle, and sets the obtained logical XOR as a data value of the regenerated data sequence for the current cycle.

9. The transmission system as set forth in claim 7, wherein

the frequency divider obtains the frequency-divided signal by dividing the frequency of the negative pulse into half, and outputs the obtained frequency-divided signal, and

the data regenerating section obtains a negation of a logical XOR between a logical value of the frequency-divided signal for a current cycle and a logical value of the frequency-divided signal for an immediately previous cycle, and sets the obtained negation of the logical XOR as a data value of the regenerated data sequence for the current cycle.

10. The transmission system as set forth in claim 6, wherein

the receiver includes:

a positive frequency divider that obtains a positive frequency-divided signal by dividing a frequency of the positive pulse into half and outputs the obtained positive frequency-divided signal; and

a negative frequency divider that obtains a negative frequency-divided signal by dividing a frequency of the negative pulse into half and outputs the obtained negative frequency-divided signal,

the clock generating section generates the reception clock by calculating a logical XOR between the positive and negative frequency-divided signals, and

the receiver further includes;

a signal obtaining section that obtains one of the positive and negative frequency-divided signals at rising and falling edges of the reception clock; and

a data regenerating section that regenerates the data sequence based on the frequency-divided signal obtained by the signal obtaining section.

11. The transmission system as set forth in claim 6, wherein

the receiver includes

an SR flip-flop that is set by the positive pulse detected by the positive pulse detecting section and reset by the negative pulse detected by the negative pulse detecting section, thereby outputting an SR signal.

12. The transmission system as set forth in claim 6, wherein

the receiver includes:

a positive pulse obtaining section that obtains an output from the positive pulse detecting section at a timing designated by the reception clock;

a negative pulse obtaining section that obtains an output from the negative pulse detecting section at the timing designated by the reception clock; and

a data regenerating section that regenerates a value of each of the pieces of data based on outputs from the positive and negative pulse obtaining sections.

13. The transmission system as set forth in claim 6, wherein

the receiver includes

a positive pulse obtaining section that obtains an output from the positive pulse detecting section at a timing designated by the reception clock, and

the receiver outputs an output from the positive pulse obtaining section as a value of each of the pieces of data.

14. The transmission system as set forth in claim 5, wherein

the transmitter obtains a converted data sequence by (i) adding data having a logical value of H at a start of the data sequence to transmit and (ii) calculating a logical XOR between a logical value of data of the data sequence for a current cycle and a logical value of data of the data sequence for an immediately previous cycle, converts each of pieces of data included in the obtained converted data sequence into a pulse having a polarity determined by a value of the each piece of data, and transmits the pulse,

the receiver includes:

a positive pulse detecting section that detects a positive pulse from the received transmission signal, the positive pulse having the signal level on a positive side;

a negative pulse detecting section that detects a negative pulse from the received transmission signal, the negative pulse having the signal level on a negative side;

a clock generating section that generates a reception clock based on the timing edge of the positive pulse detected by the positive pulse detecting section and the timing edge of the negative pulse detected by the negative pulse detecting section;

a frequency divider that obtains a frequency-divided signal by dividing a frequency of one of the positive and negative pulses into half and outputs the obtained frequency-divided signal; and

a signal obtaining section that obtains the frequency-divided signal at a timing designated by the reception clock, and

the receiver outputs the frequency-divided signal obtained by the signal obtaining section as the data sequence.

15. A transmitter that transmits a transmission signal which is generated by converting pieces of data included in a data sequence to transmit into data waveforms each of which has (i) a level signal whose signal level is determined by a value of a corresponding one of the pieces of data and (ii) a timing edge indicating a timing to obtain the level signal.

16. A receiver that receives a transmission signal transmitted thereto, the transmission signal being generated by converting pieces of data included in a data sequence into data waveforms each of which has (i) a level signal whose signal level is determined by a value of a corresponding one of the pieces of data and (ii) a timing edge indicating a timing to obtain the level signal, wherein

the receiver detects the signal level of each of the data waveforms of the transmission signal at the timing designated by the timing edge of the each data waveform, and outputs a data value corresponding to the detected signal level.

17. A transmission method for transmitting a data sequence, comprising:

transmitting a transmission signal which is generated by converting pieces of data included in the data sequence into data waveforms each of which has (i) a level signal whose signal level is determined by a value of a corresponding one of the pieces of data and (ii) a timing edge indicating a timing to obtain the level signal; and

detecting the signal level of each of the data waveforms of the transmission signal at the timing designated by the timing edge of the each data waveform, and outputting a data value corresponding to the detected signal level.