JPH10215285A - Data slicer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the data slicer that extracts an optimum base band signal independently of a state of data being a radio demodulation output. SOLUTION: The data slicer comprises a time constant circuit section 106 consisting of combinations at least two sets of resistors 109, 110 and capacitors 107, 108, switches 102-105, and a control section 111, and the control section 111 controls the time constant circuit section 106 such that charging of one time constant circuit (integration circuit) is stopped and then charging or the other time constant circuit is stopped after the lapse of time of one set of data being the radio demodulation output to add outputs of both the time constant circuits in the time constant circuit section 106, slice levels 115, 116 are set to a midpoint of the amplitude of the data being the radio demodulation output and an optimum base band signal 112 is extracted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data slicer for extracting an optimum baseband signal irrespective of the state of a continuous 0, 1 signal (preamble).

[0002]

2. Description of the Related Art FIG. 9 shows a block diagram of a conventional data slicer. In FIG. 9, 1 is a comparator for comparing the voltage levels of the reference voltage and the input voltage and outputting the result, 2 is a resistor, 3 is a capacitor, 4 is a switch, 5 is a control unit, and 6 is output from the comparator. Baseband signal, 7 is a radio demodulation signal, 8 is ON / OFF of switch 4
, And a time constant circuit (integrating circuit) is constituted by the resistor 2 and the capacitor 3. Reference numeral 9 denotes a slice level (reference voltage of the comparator 1). The comparator 1 compares the voltage level of the slice level 9 with the voltage level of the radio demodulation signal 7 and outputs the result as a baseband signal 6. The operation of the data slicer configured as described above will be described below.

FIGS. 10, 11 and 12 are diagrams showing the relationship between a radio demodulation signal, a slice level, a baseband signal, and a time constant of a conventional data slicer, and show a baseband signal 6, a radio demodulation signal 7, and a control signal. 8 shows the relationship between a time constant circuit composed of a resistor 8, a resistor 2, and a capacitor 3.
Voltage level 10 is the midpoint of the amplitude of wireless demodulated signal 7,
When the DC voltage of the voltage level 10 is applied to the resistor 2 and the capacitor 3 in place of the wireless demodulation signal 7 while the switch 4 is in the ON state, the slice level 9 reaches the voltage level 10 by forming a curve like a curve 11. . 10 shows a case where the time constant is small, FIG. 11 shows a case where the time constant is medium, and FIG. 12 shows a case where the time constant is large.

In FIG. 9, a radio demodulated signal 7 is connected to a (+) side input of a comparator 1 and a switch 4.
Switch 4 is ON only when control signal 8 is enabled
Switch 4 is OFF when disabled.
Becomes When the switch 4 is in the ON state, it is charged by the resistor 2 and the capacitor 3, and the outputs of the resistor 2 and the capacitor 3 are connected to the (−) side input of the comparator 1. When the switch 4 is turned off, the slice level 9 is fixed, and it is determined whether the voltage level of the (+) side input (wireless demodulation signal 7) of the comparator 1 is higher or lower than the fixed slice level 9. Baseband signal 6
Is output as

FIG. 10 shows a case where the time constants of the resistor 2 and the capacitor 3 are small. Since the time constant is small, the amplitude of the wireless demodulated signal 7 immediately reaches the midpoint (voltage level 10) after the switch 4 is turned on, but follows the waveform of the wireless demodulated signal 7 too much. Therefore, when the switch 4 is turned off at any point, the wireless demodulated signal 7
, The slice level 9 is fixed at a position deviated from the middle point of the amplitude (voltage level 10), and the duty ratio of the baseband signal 6 output as a result is not 50%. If the duty ratio is not 50%, errors occur in clock reproduction and data recognition, resulting in poor communication quality and the like.

FIG. 12 shows a case where the time constants of the resistor 2 and the capacitor 3 are large. Since the time constant is large, the amplitude of the wireless demodulation signal 7 does not immediately reach the midpoint (voltage level 10) after the switch 4 is turned on, but hardly follows the waveform of the wireless demodulation signal 7. Therefore, even if the switch 4 is turned off at an arbitrary position, the slice level 9 is fixed at a position substantially at the midpoint (voltage level 10) of the amplitude of the radio demodulation signal 7, and the resulting baseband signal 6 is output. The duty ratio becomes approximately 50%. However, in this case, a sufficient time is required to reach the middle point (voltage level 10) of the amplitude of the radio demodulation signal 7, and if the switch is turned off before this time, the radio demodulation signal 7
Is lower than the midpoint of the amplitude (voltage level 10), the slice level 9 is obtained, and the duty ratio of the baseband signal 6 at this time is not 50%.

FIG. 11 shows a case where the time constants of the resistor 2 and the capacitor 3 are set to be medium. Since the time constant is medium, the middle point (voltage level 10) of the amplitude of the wireless demodulation signal 7 after the switch 4 is turned on reaches later than the case where the time constant is small and earlier than the case where the time constant is large. The waveform of the signal 7 does not follow when the time constant is small, but follows when the time constant is large. Normally, it reaches the middle point (voltage level 10) of the amplitude of the wireless demodulation signal 7 within a certain period of time, follows the waveform of the wireless demodulation signal 7, and switches the switch 4 at any point.
The values of the resistor 2 and the capacitor 3 (within the time constant) are determined so that the slice level 9 becomes a level close to the middle point even after flip-flop.

[0008]

In the above-mentioned conventional data slicer, if a continuous signal of 0 and 1 (preamble) is lost due to the radio wave condition, it reaches the middle point (voltage level 10) of the amplitude of the radio demodulated signal 7. However, since the baseband signal 6 follows the waveform of the wireless demodulation signal 7 to some extent, the duty ratio of the baseband signal 6 does not reach 50%, and the communication quality and the like deteriorate.

Therefore, the present invention solves such a problem,
It is an object of the present invention to provide a data slicer capable of extracting an optimum baseband signal regardless of the state of a continuous signal (preamble) of 0 and 1.

[0010]

According to the first aspect of the present invention,
The wireless demodulation signal is connected to one input of a comparator for comparing a voltage level between a reference voltage and an input voltage and outputting the result and an input of a first switch and a second switch, and the first switch and the An output of the second switch is connected to an input of a time constant circuit unit including at least two sets of resistors and capacitors, and an output of the time constant circuit unit is connected to a third terminal.
And the input of the fourth switch are connected to the input of the third switch and the output of the fourth switch to the other input of the comparator. After turning on the first switch and the second switch to charge the time constant circuit section during the period of turning on, turning off the first switch, and after a lapse of one data, the second switch Switch off
And turns on the third switch and the fourth switch.
Control so that

According to a second aspect of the present invention, the output of the comparator is connected to the input of a time measuring unit for measuring various times such as the time for one data, and the output of the time measuring unit is sent to the control unit. And the control unit charges the time constant circuit unit by turning on the first switch and the second switch while the signals of 0 and 1 are continuous, and turns off the first switch. Then, after a lapse of one data measured by the time measuring unit, the second switch is turned off and the third switch and the fourth switch are controlled to be turned on.

According to a third aspect of the present invention, after the first switch is turned off, the second switch is turned off after an elapse of an odd multiple of the time for one data, and the third switch and the third switch are turned off. Control is performed so as to turn on the fourth switch.

According to a fourth aspect of the present invention, the control is performed such that the third switch or the fourth switch is always turned on.

According to a fifth aspect of the present invention, there are provided a plurality of switches, and the time constant circuit section comprises a plurality of resistors and capacitors.

According to a sixth aspect of the present invention, a transistor circuit is used for the switch.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 has a time constant circuit section, a switch, and a control section. The control section includes a resistor and a capacitor of the time constant circuit section.
After the input switch of one set of integration circuits is turned on and charged, and the input switch of one of the integration circuits is turned off, and after the lapse of one data, the input switch of the other integration circuit is turned off. When the outputs of the two integrators are added, the reference signal of the comparator is always at the midpoint of the amplitude of the wireless demodulated signal, and an optimal baseband signal having a duty ratio of 50% can be extracted.

According to a second aspect of the present invention, there is provided a time constant circuit unit,
It has a switch, a time measurement unit, and a control unit. The time measurement unit measures the time corresponding to one data of 0 and 1, and the control unit includes a resistor and a capacitor of a time constant circuit unit. After the input switches of the two integrating circuits are turned on to charge the battery, the input switch of one of the integrating circuits is turned off, and after the time of one data measured by the time measuring unit has elapsed, the other integrating circuit is charged. Since the input switch is turned off, when the outputs of the two integrators are added, the reference signal of the comparator is always at the midpoint of the amplitude of the wireless demodulated signal, and an optimum baseband signal having a duty ratio of 50% can be extracted.

According to a third aspect of the present invention, there is provided a time constant circuit section,
A switch and a control unit. In the control unit, the input switch of the two integration circuits including the resistor and the capacitor of the time constant circuit unit is turned on to charge, and the input switch of one of the integration circuits is turned on. After turning OFF, the input switch of the other integrating circuit is turned OFF after a lapse of an odd multiple of one data. Therefore, when the outputs of the two integrating circuits are added, the reference signal of the comparator always becomes the amplitude of the radio demodulated signal. An optimum baseband signal having a middle point and a duty ratio of 50% can be extracted.

According to a fourth aspect of the present invention, there is provided a time constant circuit section,
A switch and a control unit. The control unit turns on the input switches of the two integration circuits each configured by a resistor and a capacitor of the time constant circuit unit to charge them, and sets the output switch of one of the integration circuits to ON. After turning on the input switch of the integrating circuit and turning off the input switch of the other integrating circuit after a lapse of one data, the reference signal of the comparator is obtained by adding the outputs of the two integrating circuits. Can always be at the midpoint of the amplitude of the wireless demodulated signal, and an optimum baseband signal with a duty ratio of 50% can be extracted.

According to a fifth aspect of the present invention, there is provided a time constant circuit section,
A switch and a control unit. The control unit turns on input switches of a plurality of integration circuits each including a resistor and a capacitor of the time constant circuit unit to charge the integration circuit. Turn off half of the input switches
After that, the input switches of the remaining half of the integrating circuits are turned off after the lapse of one data, so that the variation in the values of the resistors and capacitors constituting the time constant circuit can be absorbed.
By summing the outputs of all the integrating circuits, it is possible to extract the optimum baseband signal in which the reference signal of the comparator always becomes the middle point of the amplitude of the radio demodulated signal and the duty ratio becomes 50%.

According to a sixth aspect of the present invention, there is provided a time constant circuit section,
A transistor circuit unit and a control unit, wherein the control unit controls the transistor circuit so that the wireless demodulation signal is input and charged to two integration circuits each configured by a resistor and a capacitor of the time constant circuit unit; After controlling so as not to input the wireless demodulation signal to one of the integrating circuits, after the lapse of one data, the wireless demodulating signal is not input to the other integrating circuit, and the outputs of the two integrating circuits are changed. By controlling so as to input to the reference voltage of the comparator, it is possible to take out the optimum baseband signal in which the reference voltage of the comparator always becomes the middle point of the amplitude of the radio demodulation signal and the duty ratio becomes 50%.

(Embodiment 1) FIG. 1 is a block diagram of a data slicer according to Embodiment 1 of the present invention, and FIG. 2 is a relationship diagram of a radio demodulated signal, a slice level, and a baseband signal of the data slicer.

In FIG. 1, reference numeral 101 denotes a comparator for comparing the voltage levels of a reference voltage and an input voltage and outputting the result, 102, 103, 104, and 105 switches,
109 and 110 are resistors, 107 and 108 are capacitors,
106 denotes resistors 109 and 110 and capacitors 107 and 1
08, a time constant circuit section 111, a switch 102,
A control unit that controls 103, 104, and 105 includes a baseband signal output from the comparator 101,
13 is a radio demodulated signal, 114 is switches 102 and 10
Control signals 115 and 116 for controlling ON / OFF of 3, 104 and 105 are slices which are outputs from a time constant circuit (integrating circuit) composed of a resistor 109 and a capacitor 107 and a resistor 110 and a capacitor 108, respectively. Level. FIG. 2 shows a wireless demodulation signal 113, a baseband signal 112, a control signal 114, and a slice level 11.
5, 116 are shown.

The operation of the data slicer configured as described above will be described below. 2, reference numeral 117 denotes a voltage level at the midpoint of the amplitude of the wireless demodulation signal 113. When the switches 104 and 105 are ON, the wireless demodulated signal 113
Instead, when a DC voltage of voltage level 117 is applied to the resistor 109 and the capacitor 106, the slice level 1
15 and 116 reach a voltage level 117 in a curve such as a curve 118. Here, for convenience, the switch 10 is used only for two periods of continuous data (preamble) of 0,1.
If 4,105 is ON, the slice level 115,
So that resistor 116 reaches voltage level 117,
It is assumed that the values of 110 and capacitors 107 and 108 are determined.

The control method will be described.
Switches 104 and 105 are turned ON at a predetermined position or an arbitrary position of continuous data (preamble) of 0 and 1
I do. If the switches 104 and 105 are turned on only for two periods of continuous data (preamble) of 0 and 1, the resistors 109 and 110 and the capacitors 107 and 1 are set so that the slice levels 115 and 116 reach the voltage level 117.
Since the value of 08 is determined, the switch 104 is turned off when the time equal to or more than two times of continuous data (preamble) of 0 and 1 has elapsed. Then, switch 104 is set to O
After a lapse of one bit of data from the FF, the switch 105 is turned off and the switches 102 and 103 are turned on.

By controlling in this manner, the switch 104
Is turned off at an arbitrary time, the switch 10 is turned off after a lapse of one bit of data.
4 and the potential difference between the slice level 115 when the switch 105 is turned off and the midpoint (voltage level 117) of the amplitude of the wireless demodulated signal 113 and the amplitude between the slice level 116 and the amplitude of the wireless demodulated signal 113 when the switch 105 is turned off. The potential difference from the point (voltage level 117) is always equal as shown in FIG. Therefore, when the switches 102 and 103 are turned on, the slice levels 115 and 116 are added, and the (−) side input of the comparator 101 is always equal to the midpoint of the amplitude of the wireless demodulation signal 113 (voltage level 117). Therefore, the baseband signal 112 output from the comparator 101
Has a duty ratio of 50%.

Here, the case where the switch 105 is turned off after the switch 104 is turned off has been described. However, when the switch 104 is turned off after the switch 105 is turned off, the baseband signal 112 output from the comparator 101 is also a duty. The ratio becomes 50%.

(Embodiment 2) FIG. 3 is a block diagram of a data slicer according to Embodiment 2 of the present invention. Reference numeral 201 denotes a time measuring unit that measures the time for one bit of the data of 0 and 1 of the baseband signal 112, and the other configuration is the same as that of the first embodiment.

The operation of the data slicer configured as described above will be described below. The time measuring unit 201 measures the time corresponding to one bit of the data of 0 and 1 of the baseband signal 112 and notifies the control unit 111 of the result. Control unit 1
Reference numeral 11 denotes a switch 104, 10 at a predetermined position of the continuous data (preamble) of 0, 1 or at an arbitrary position.
Turn 5 ON. When the switches 104 and 105 are turned ON only for two periods of continuous data (preamble) of 0 and 1, the slice levels 115 and 116 become the voltage level 11
7 and the resistors 109 and 110 and the capacitor 1
Since the values of 07 and 108 are determined, the switch 104 is turned off when a time equal to or more than two times of continuous data (preamble) of 0 and 1 has elapsed. And the switch 10
4 is turned off, and after a lapse of one bit of data measured by the time measuring unit 201, the switch 105 is turned off.
F. Control is performed so that switches 102 and 103 are turned on.

By controlling in this manner, the switch 104
And the potential difference between the slice level 115 and the midpoint of the amplitude of the wireless demodulation signal 113 (voltage level 117) when the switch 105 is turned off, and the midpoint between the slice level 116 and the amplitude of the radio demodulation signal 113 when the switch 105 is turned off. The potential difference from (voltage level 117) is always equal as shown in FIG.
Therefore, by turning on the switches 102 and 103, the slice levels 115 and 116 are added and the comparator 1
The (−) side input of 01 is always equal to the midpoint (voltage level 117) of the amplitude of the wireless demodulation signal 113. Accordingly, even when the time of one bit of continuous data (preamble) of 0 and 1 is unknown or has changed, the comparator 101 does not.
Has a duty ratio of 50%.

(Embodiment 3) FIG. 4 is a diagram showing a relationship among a radio demodulated signal, a slice level, and a baseband signal of a data slicer according to Embodiment 3 of the present invention. In FIG.
The control unit 111 performs continuous data of 0 and 1 (preamble).
Switch 10 at a predetermined position or an arbitrary position.
4, 105 is turned ON. The switches 104 and 105 are turned off only during a period of two consecutive data (preamble) of 0 and 1
When N is set, the values of the resistors 109 and 110 and the capacitors 107 and 108 are determined so that the slice levels 115 and 116 reach the voltage level 117.
When a time equal to or more than two times of one continuous data (preamble) has elapsed, the switch 104 is turned off. Then, after elapse of an odd multiple of the time of one bit of data after turning off the switch 104 (here, three bits), control is performed so that the switch 105 is turned off and the switches 102 and 103 are turned on.

By controlling in this manner, the switch 104
And the potential difference between the slice level 115 and the midpoint of the amplitude of the wireless demodulation signal 113 (voltage level 117) when the switch 105 is turned off, and the midpoint between the slice level 116 and the amplitude of the radio demodulation signal 113 when the switch 105 is turned off. The potential difference from (voltage level 117) is always equal as shown in FIG.
Therefore, by turning on the switches 102 and 103, the slice levels 115 and 116 are added and the comparator 1
The (−) side input of 01 is always equal to the midpoint (voltage level 117) of the amplitude of the wireless demodulation signal 113. Therefore, the duty ratio of the baseband signal 112 output from the comparator 101 is 50%.

(Embodiment 4) FIG. 5 is a diagram showing a relationship among a radio demodulated signal, a slice level, and a baseband signal of a data slicer according to Embodiment 4 of the present invention. In FIG.
The control unit 111 keeps the switch 102 ON at all times,
Switches 104 and 105 are turned ON at a predetermined position or an arbitrary position of continuous data (preamble) of 0 and 1
I do. If the switches 104 and 105 are turned on only for two periods of continuous data (preamble) of 0 and 1, the resistors 109 and 110 and the capacitors 107 and 1 are set so that the slice levels 115 and 116 reach the voltage level 117.
Since the value of 08 is determined, the switch 104 is turned off when the time equal to or more than two times of continuous data (preamble) of 0 and 1 has elapsed. Then, switch 104 is set to O
After a lapse of one bit of data from the FF, the switch 105 is turned off and the switch 103 is turned on.

By controlling as described above, the switch 104
And the potential difference between the slice level 115 and the midpoint of the amplitude of the wireless demodulation signal 113 (voltage level 117) when the switch 105 is turned off, and the midpoint between the slice level 116 and the amplitude of the radio demodulation signal 113 when the switch 105 is turned off. The potential difference from (voltage level 117) is always equal as shown in FIG.
Therefore, when the switch 103 is turned on, the slice levels 115 and 116 are added, and the (−) side input of the comparator 101 always becomes equal to the middle point (voltage level 117) of the amplitude of the wireless demodulation signal 113. Therefore, the duty ratio of the baseband signal 112 output from the comparator 101 is 50%.

(Embodiment 5) FIG. 6 is a block diagram of a data slicer according to Embodiment 5 of the present invention, and FIG. 7 is a diagram showing a relationship between a radio demodulated signal, a slice level, and a baseband signal of the data slicer. In FIG. 6, 301, 30
2,303,304,305,306,307,308
Are switches, 313, 314, 315, 316 are resistors,
309, 310, 311 and 312 are capacitors, 31
7,318,319,320 are slice levels,
Other configurations are the same as in the first embodiment. Here, for convenience,
When the switches 305, 306, 307, and 308 are turned ON only for two periods of continuous data (preamble) of 0 and 1, the slice levels 317, 318, 319, and 32 are set.
The resistances 313 and 31 are set so that 0 reaches the voltage level 117.
4,315,316 and capacitors 309,310,3
It is assumed that the values of 11, 312 have been determined.

The operation of the data slicer configured as described above will be described below. The control unit 111 controls the switches 305, 306, 307, 30 at predetermined positions or arbitrary positions of continuous data (preamble) of 0, 1
8 is turned ON. Switches 305, 306, 307, 3 only for two periods of continuous data (preamble) of 0, 1
08 is ON, the slice level 317, 31
8, 319, 320 reach voltage level 117, resistors 313, 314, 315, 316 and capacitor 3
Since the values of 09, 310, 311 and 312 are determined, the switches 305, 306, 307,
The switches 305 and 306 of the half of 308 are turned off.
After turning off the switches 305 and 306, the remaining half of the switches 3
07, 308 and switches 301, 302, 30
Control is performed so that 3, 304 is turned on.

By controlling in this manner, the switch 30
Slice level 31 when 5,306 is turned off
7, 318 and the midpoint (voltage level 117) between the slice levels 319, 320 and the amplitude of the radio demodulation signal 113 when the switches 307, 308 are turned off. The potential difference from level 117) is always equal as shown in FIG. Therefore, when the switches 301, 302, 303, 304 are turned on, the slice levels 317, 318, 319, 320 are added, and the (−) side input of the comparator 101 is always at the midpoint of the amplitude of the radio demodulated signal 113 (voltage level 117). ). Thereby, the resistors 313, 314, 315, 316
Even when the values of the capacitors 309, 310, 311 and 312 vary, the duty ratio of the baseband signal 112 output from the comparator 101 is 50%.
Becomes

Here, the case where the number of time constant circuits (integrating circuits) constituting the time constant circuit unit 106 is four has been described. However, the baseband signal 112 output from the comparator 101 is similarly used in the case of a larger number of sets. The duty ratio becomes 50%.

(Embodiment 6) FIG. 8 is a block diagram of a data slicer according to Embodiment 6 of the present invention. 401,
402, 403, and 404 are transistor circuit units;
Other configurations are the same as in the first embodiment. Here, for convenience,
If the transistor circuits 403 and 404 are ON only for two periods of continuous data (preamble) of 0 and 1, the resistors 109 and 110 and the capacitor 10 are connected so that the slice levels 115 and 116 reach the voltage level 117.
It is assumed that the values of 7, 108 are determined.

The operation of the data slicer configured as described above will be described below. The control unit 111 activates the transistor circuit units 403 and 404 at predetermined positions of the continuous data (preamble) of 0 and 1 or at an arbitrary position.
N. If the transistor circuit units 403 and 404 are turned ON only for two periods of continuous data (preamble) of 0 and 1, the resistors 109 and 110 and the capacitors 107 and 108 make the slice levels 115 and 116 reach the voltage level 117. Is determined, the transistor circuit portion 403 is turned off when a time equal to or more than two times of continuous data (preamble) of 0 and 1 has elapsed. After a lapse of one bit of data after turning off the transistor circuit portion 403, the transistor circuit portion 404
Is turned off and the transistor circuits 401 and 402 are turned on.

By controlling in this manner, the slice level 115 at the time when the transistor circuit unit 403 is turned off is set.
And the midpoint of the amplitude of the radio demodulated signal 113 (voltage level 11
7) and the transistor circuit unit switch 105
The potential difference between the slice level 116 and the midpoint of the amplitude of the wireless demodulation signal 113 (voltage level 117) at the time when is turned off is always equal as shown in FIG. Therefore, by turning on the transistor circuits 401 and 402, the slice levels 115 and 116 are added, and the (−) side input of the comparator 101 is always equal to the midpoint of the amplitude of the radio demodulation signal 113 (voltage level 117). Therefore, the duty ratio of the baseband signal 112 output from the comparator 101 is 50%.

[0042]

According to the present invention, by providing a time constant circuit section, a time measuring section, a transistor circuit section, and the like,
An optimum baseband signal can be extracted regardless of the state of a continuous signal (preamble) of 0 and 1.

[Brief description of the drawings]

FIG. 1 is a block diagram of a data slicer according to a first embodiment of the present invention.

FIG. 2 is a relationship diagram of a wireless demodulated signal, a slice level, and a baseband signal of the data slicer according to the first embodiment of the present invention.

FIG. 3 is a block diagram of a data slicer according to a second embodiment of the present invention;

FIG. 4 is a diagram illustrating a relationship among a wireless demodulated signal, a slice level, and a baseband signal of a data slicer according to a third embodiment of the present invention.

FIG. 5 is a relationship diagram of a wireless demodulated signal, a slice level, and a baseband signal of a data slicer according to a fourth embodiment of the present invention.

FIG. 6 is a block diagram of a data slicer according to a fifth embodiment of the present invention.

FIG. 7 is a relationship diagram of a wireless demodulated signal, a slice level, and a baseband signal of a data slicer according to a fifth embodiment of the present invention.

FIG. 8 is a block diagram of a data slicer according to a sixth embodiment of the present invention.

FIG. 9 is a block diagram of a conventional data slicer.

FIG. 10 is a diagram showing a relationship among a radio demodulation signal, a slice level, a baseband signal, and a time constant of a conventional data slicer.

FIG. 11 is a diagram showing the relationship between a radio demodulated signal, a slice level, a baseband signal, and a time constant of a conventional data slicer.

FIG. 12 is a relational diagram of a radio demodulation signal, a slice level, a baseband signal, and a time constant of a conventional data slicer.

[Explanation of symbols]

 101 Comparator 102, 103, 104, 105 Switch 106 Time constant circuit unit 107, 108 Capacitor 109, 110 Resistance 111 Control unit 112 Baseband signal 113 Radio demodulation signal 114 Control signal 115, 116 Slice level 401, 402, 403, 404 Transistor Circuit section

Claims (6)

[Claims] A first demodulator for comparing a voltage level between a reference voltage and an input voltage and outputting the result to one input of a comparator and an input of a first switch and a second switch; The outputs of the first switch and the second switch are connected to the inputs of a time constant circuit section composed of at least two sets of resistors and capacitors, and the outputs of the time constant circuit section are connected to the third switch and the fourth switch. Connecting the output of the third switch and the output of the fourth switch to the other input of the comparator;
In a control unit, the time constant circuit unit is charged by turning on the first switch and the second switch while the signals of 0 and 1 are continuous, and after turning off the first switch, A data slicer which controls to turn off the second switch and turn on the third switch and the fourth switch after a lapse of one time. 2. An output of the comparator is connected to an input of a time measuring unit for measuring various times such as a time for one data, and an output of the time measuring unit is connected to the control unit. In the above, during the period in which the signals of 0 and 1 are continuous, the first switch and the second switch are turned on to charge the time constant circuit unit, and after the first switch is turned off, the time measurement is performed. 2. The control of turning off the second switch and turning on the third switch and the fourth switch after a time corresponding to one data measured by the unit has elapsed. 3. Data slicer as described. 3. After turning off the first switch, after a lapse of an odd multiple of the time of one data, the second switch is turned off, and the third switch and the fourth switch are turned off. 3. The data slicer according to claim 1, wherein the data slicer is controlled to be turned on. 4. The data slicer according to claim 1, wherein the control is performed such that the third switch or the fourth switch is always turned on. 5. The data slicer according to claim 1, wherein there are a plurality of said switches, and said time constant circuit section comprises a plurality of resistors and capacitors. 6. The data slicer according to claim 1, wherein a transistor circuit section is used for said switch.