Phase-discriminating device and method
A high-accuracy and computational efficient phase-discriminating device is provided and includes a phase-discriminating unit. The phase-discriminating unit converts an input and a reference signals into an input and a reference sequences respectively by a one-bit A/D conversion operation, determines a first value, an in-phase component and a quadrature component of the input signal in response to the input and the reference sequences, and produces an estimated phase of the input signal according to a relation among the first value, the in-phase component and a polarity of the quadrature component, wherein the first value is a certain integer being one of a first integer and a second integer, the first integer is a sampling count of the one-bit A/D conversion operation for producing the input sequence, and the second integer is a summation of an absolute value of the in-phase component and that of the quadrature component.
1. A phase-discriminating device, comprising:
a phase-discriminating unit converting an input and a reference signals into an input and a reference sequences respectively by a one-bit A/D conversion operation, determining a first value A P , an in-phase component I P and a quadrature component Q P of the input signal in response to the input and the reference sequences, and producing an estimated phase of the input signal according to a relation among the first value A P , the in-phase component I P and a polarity of the quadrature component Q P , wherein the relation is defined by a first formula (sgn[Q P ]·(1−I P /A P )), the sgn[Q P ] denotes a polarity function, the estimated phase is proportional to the first formula (sgn[Q P ]·(1−I P /A P )) and the first value A P is a certain integer being one of:
a first integer being a sample size of the one-bit A/D conversion operation for producing the input sequence; and
a second integer being a summation of an absolute value of the in-phase component I P and an absolute value of the quadrature component Q P .
2. A phase-discriminating device according to claim 1 , wherein:
the input signal has a carrier frequency; and
the reference signal includes an in-phase and a quadrature reference waves, wherein each of the in-phase and the quadrature reference waves has the carrier frequency.
3. A phase-discriminating device according to claim 2 , wherein the first value A P is the first integer, and the phase-discriminating unit comprises:
a determining unit converting the input and the reference signals into the input and the reference sequences respectively by the one-bit A/D conversion operation, and determining the first value A P , the in-phase component I P and the quadrature component Q P in response to the input and the reference sequences; and
a phase-estimating unit electrically connected to the determining unit, calculating a second value equal to (sgn[Q P ]·(1−I P /A P )/2), and multiplying the second value by π to produce the estimated phase.
4. A phase-discriminating device according to claim 2 , wherein the first value A P is the second integer, and the phase-discriminating unit comprises:
a determining unit converting the input and the reference signals into the input and the reference sequences respectively by the one-bit A/D conversion operation, and determining the in-phase component Ip and the quadrature component Q P in response to the input and the reference sequences; and
a phase-estimating unit electrically connected to the determining unit, calculating the second integer, calculating a second value equal to (sgn[Q P ]·(1−I P /A P )/2), and multiplying the second value by n to produce the estimated phase.
5. A phase-discriminating device, comprising:
a phase-discriminating unit processing an input signal by a one-bit A/D conversion operation to determine a first value A P , an in-phase component I P and a quadrature component Q P of the input signal, and producing an estimated phase of the input signal according to a relation among the first value A P , the in-phase component I P and a polarity of the quadrature component Q P , wherein the relation is defined by a first formula (sgn[Q P ]·(1−I P /A P )), the sgn[Q P ] denotes a polarity function, the first value A P is associated with a signal-to-noise ratio of the input signal, and the estimated phase is proportional to the first formula (sgn[Q P ]·(1−I P /A P )).
6. A phase-discriminating device according to claim 5 , wherein:
the phase-discriminating unit determines a reference signal according to the input signal, converts the input and the reference signals into an input and a reference sequences respectively by the one-bit A/D conversion operation, and determines the first value A P , the in-phase component I P and the quadrature component Q P in response to the input and the reference sequences;
the input signal has a carrier frequency;
the reference signal includes an in-phase and a quadrature reference waves, wherein each of the in-phase and the quadrature reference waves has the carrier frequency;
the reference sequence includes an in-phase and a quadrature reference sequences; and
each of the input, the in-phase and the quadrature reference sequences has a high and a low bit values being 1 and −1 respectively.
7. A phase-discriminating device according to claim 6 , wherein the signal-to-noise ratio is larger than 10 dB, the first value A P is an integer being a sample size of the one-bit A/D conversion operation for producing the input sequence, and the phase-discriminating unit comprises:
a determining unit converting the input and the reference signals into the input and the reference sequences respectively by the one-bit A/D conversion operation, and determining the first value A P , the in-phase component I P and the quadrature component Q P in response to the input and the reference sequences; and
a phase-estimating unit electrically connected to the determining unit, calculating a second value equal to (sgn[Q P ]·(1−I P /A P )/2), and multiplying the second value by π to produce the estimated phase.
8. A phase-discriminating device according to claim 7 , wherein the determining unit comprises:
an A/D converter receiving the input signal, determining the reference signal according to the input signal, and sampling the input signal and the in-phase and the quadrature reference waves by a number of times equal to the sample size of the one-bit A/D conversion operation to respectively produce the input, the in-phase and the quadrature reference sequences;
a first XOR gate producing a first sequence having corresponding bit values in response to the input and the in-phase reference sequences;
a second XOR gate producing a second sequence having corresponding bit values in response to the input and the quadrature reference sequences;
a first counter device accumulating the corresponding bit values of the first sequence to produce the in-phase component I P ; and
a second counter device accumulating the corresponding bit values of the second sequence to produce the quadrature component Q P .
9. A phase-discriminating device according to claim 7 , wherein the phase-estimating unit comprises:
an addition circuit receiving the in-phase component I P and the sample size from the determining unit, and subtracting the in-phase component I P from the sample size to produce a third value;
a first multiplication circuit receiving the sample size, and multiplying the sample size by 2 to produce a fourth value;
a division circuit receiving the third value and the fourth value, and dividing the third value by the fourth value to produce a fifth value;
a polarity determining circuit receiving the quadrature component Q P , and producing a sixth value of the sgn[Q P ];
a second multiplication circuit receiving the fifth value and the sixth value, and multiplying the fifth value by the sixth value to produce the second value; and
a third multiplication circuit receiving the second value, and multiplying the second value by π to produce the estimated phase.
10. A phase-discriminating device according to claim 6 , wherein the first value A P is an integer being a summation of an absolute value of the I P and an absolute value of the Q P , and the phase-discriminating unit comprises:
a determining unit converting the input and the reference signals into the input and the reference sequences respectively by the one-bit A/D conversion operation, and determining the in-phase component I P and the quadrature component Q P in response to the input and the reference sequences; and
a phase-estimating unit electrically connected to the determining unit, calculating the first value A P , calculating a second value equal to (sgn[Q P ]·(1−I P /A P )/2), and multiplying the second value by n to produce the estimated phase.
11. A phase-discriminating device according to claim 10 , wherein the determining unit comprises:
an A/D converter receiving the input signal and the in-phase and the quadrature reference waves, and sampling the input signal and the in-phase and the quadrature reference waves by a number of times equal to a sample size of the one-bit A/D conversion operation to respectively produce the input, the in-phase and the quadrature reference sequences;
a first XOR gate producing a first sequence having corresponding bit values in response to the input and the in-phase reference sequences;
a second XOR gate producing a second sequence having corresponding bit values in response to the input and the quadrature reference sequences;
a first counter device accumulating the corresponding bit values of the first sequence to produce the in-phase component I P ; and
a second counter device accumulating the corresponding bit values of the second sequence to produce the quadrature component Q P .
12. A phase-discriminating device according to claim 10 , wherein the phase-estimating unit comprises:
a first operation circuit producing a third and a fourth values in response to the in-phase component I P ;
a second operation circuit producing the second value in response to the quadrature component I Q and the third and the fourth values; and
a first multiplication circuit receiving the second value, and multiplying the second value by π to produce the estimated phase.
13. A phase-discriminating device according to claim 12 , wherein the first operation circuit comprises:
a polarity determining circuit receiving the in-phase component I P , and producing a fifth value of the sgn[I P ];
an NOT gate receiving the fifth value, and producing a sixth value;
an absolute-value determining circuit receiving the in-phase component I P , and calculating an absolute value of the in-phase component I P to produce the third value; and
a multiplication circuit receiving the third value and the sixth value, and multiplying the third value by the sixth value to produce the fourth value.
14. A phase-discriminating device according to claim 12 , wherein the second operation circuit comprises:
an absolute-value determining circuit receiving the quadrature component Q P , and calculating an absolute value of the quadrature component Q P to produce a fifth value;
a first addition circuit receiving the third value and the fifth value, and adding the third value and the fifth value to produce the first value A P ;
a second addition circuit receiving the fourth value and the first value A P , and adding the fourth value and the first value A P to produce a sixth value;
a first multiplication circuit receiving the first value A P , and multiplying the first value A P by 2 to produce a seventh value;
a division circuit receiving the sixth value and the seventh value, and dividing the sixth value by the seventh value to produce an eighth value;
a polarity determining circuit receiving the quadrature component Q P , and producing a ninth value of the sgn[Q P ]; and
a second multiplication circuit receiving the eighth value and the ninth value, and multiplying the eighth value by the ninth value to produce the second value.
15. A phase-discriminating method, comprising steps of:
(a) processing an input signal by a one-bit A/D conversion operation to determine a first value A P , an in-phase component I P and a quadrature component Q P of the input signal; and
(b) producing an estimated phase of the input signal according to a relation among the first value A P , the in-phase component I P and a polarity of the quadrature component Q P , wherein the relation is defined by a first formula (sgn[Q P ]·(1−I P /A P )), the sgn[Q P ] denotes a polarity function, the first value A P is associated with a signal-to-noise ratio of the input signal, and the estimated phase is proportional to the first formula (sgn[Q P ]·(1−I P /A P )).
16. A phase-discriminating method according to claim 15 , wherein the step (a) further comprises sub-steps of:
(c) determining a reference signal according to the input signal;
(d) converting the input and the reference signals into an input and a reference sequences respectively by a one-bit A/D conversion operation;
(e) determining the first value A P , the in-phase component I P and the quadrature component Q P in response to the input and the reference sequences, wherein:
the input signal has a carrier frequency;
the reference signal includes an in-phase and a quadrature reference waves, wherein each of the in-phase and the quadrature reference waves has the carrier frequency;
the reference sequence includes an in-phase and a quadrature reference sequences; and
each of the input, the in-phase and the quadrature reference sequences has a high and a low bit values being 1 and −1 respectively.
17. A phase-discriminating method according to claim 16 , wherein the signal-to-noise ratio is larger than 10 dB, the first value A P is an integer being a sample size of the one-bit A/D conversion operation for producing the input sequence, and the step (d) further comprises a sub-step of:
sampling the input signal and the in-phase and the quadrature reference waves by a number of times equal to the sample size of the one-bit A/D conversion operation to respectively produce the input, the in-phase and the quadrature reference sequences; and
the step (e) further comprises sub-steps of:
multiplying the input sequence by the in-phase reference sequence to produce a first sequence having corresponding bit values;
multiplying the input sequence by the quadrature reference sequence to produce a second sequence having corresponding bit values;
accumulating the corresponding bit values of the first sequence to produce the in-phase component I P ; and
accumulating the corresponding bit values of the second sequence to produce the quadrature component Q P .
18. A phase-discriminating method according to claim 17 , wherein the step (b) further comprises sub-steps of:
calculating a second value equal to (sgn[Q P ]·(1−I P /A P )/2); and
multiplying the second value by π to produce the estimated phase.
19. A phase-discriminating method according to claim 17 , wherein:
the first sequence includes a plurality of bit values;
the step (e) further comprises a sub-step of counting an amount of how many the plurality of bit values equal to the low bit value;
the first formula divided by 2, (sgn[Q P ]·(1−I P /A P )/2), is equivalent to a second formula (sgn[Q P ]·(B P /A P )); and
the B P is the amount.
20. A phase-discriminating method according to claim 16 , wherein the first value A P is an integer being a summation of an absolute value of the I P and an absolute value of the Q P , and the step (b) further comprises sub-steps of:
calculating a second value equal to (sgn[Q P ]·(1−I P /A P )/2); and
multiplying the second value by π to produce the estimated phase.