Adaptive envelope extracting apparatus, signal decoding apparatus and short-distance contactless communication apparatus applying the adaptive envelope extracting apparatus, and method thereof

1. A short-distance contactless communication apparatus, comprising:

an envelope extracting apparatus, arranged to extract an envelope signal of a receiving modulation signal, wherein the envelope extracting apparatus generates a clock signal of the receiving modulation signal;

a timer, arranged to count for a frame delay time according to the envelope signal of the receiving modulation signal;

a transmitter, arranged to transmit a transmitting modulation signal when the frame delay time counted by the timer is up;

a phase-locked loop, arranged to generate a continuous clock signal according to the clock signal and the envelope signal; and

a receiver, arranged to receive the receiving modulation signal according to the continuous clock signal.

2. The short-distance contactless communication apparatus of claim 1 , wherein the timer starts to count for the frame delay time when the timer detects a rising edge of the envelope signal is generated by the envelope extracting apparatus.

3. The short-distance contactless communication apparatus of claim 1 , wherein the receiver outputs a last data bit of the receiving modulation signal to the timer, and the timer refers the last data bit to determine the frame delay time.

4. The short-distance contactless communication apparatus of claim 3 , wherein if the last data bit of the receiving modulation signal is logic “1”,the timer sets the frame delay time to be a first delay time, if the last data bit of the receiving modulation signal is logic “0”, the timer sets the frame delay time to be a second delay time, and the second delay time is different from the first delay time.

5. A short-distance contactless communication apparatus, comprising:

an envelope extracting apparatus, arranged to extract an envelope signal of a receiving modulation signal;

a timer, arranged to count for a frame delay time according to the envelope signal of the receiving modulation signal;

a transmitter, arranged to transmit a transmitting modulation signal when the frame delay time counted by the timer is up;

wherein the envelope extracting apparatus comprises: a clock extracting device, arranged to extract a clock signal of the receiving modulation signal according to a first biasing voltage; and

an edge detecting device, arranged to generate a detecting signal to indicate the envelope edge of the receiving modulation signal according to a delayed clock signal of the clock signal and a second biasing voltage;

wherein the second biasing voltage is different from the first biasing voltage.

6. The short-distance contactless communication apparatus of claim 5 , wherein the envelope extracting apparatus further comprises:

a determining device, arranged to determine a delay time and an offset voltage according to the receiving modulation signal;

wherein the delayed clock signal is generated by delaying the clock signal by the delay time, and the second biasing voltage is generated by offsetting the first biasing voltage by the offset voltage.

7. The short-distance contactless communication apparatus of claim 5 , wherein the timer starts to count for the frame delay time when the timer detects a rising edge of the envelope signal is generated by the envelope extracting apparatus.

8. A short-distance contactless communication method, comprising:

extracting an envelope signal of a receiving modulation signal, wherein extracting the envelope signal of the receiving modulation signal comprises generating a clock signal of the receiving modulation signal;

counting a frame delay time according to the envelope signal of the receiving modulation signal;

transmitting a transmitting modulation signal when the frame delay time is up;

generating a continuous clock signal according to the clock signal and the envelope signal; and

receiving the receiving modulation signal according to the continuous clock signal.

9. The short-distance contactless communication method of claim 8 , wherein the frame delay time is start to be counted when a rising edge of the envelope signal is generated.

10. The short-distance contactless communication method of claim 8 , wherein a last data bit of the receiving modulation signal is used to determine the frame delay time.

11. The short-distance contactless communication method of claim 10 , wherein if the last data bit of the receiving modulation signal is logic “1”, the frame delay time is set to be a first delay time, if the last data bit of the receiving modulation signal is logic “0”, the frame delay time is set to be a second delay time, and the second delay time is different from the first delay time.

12. A short-distance contactless communication method, comprising:

extracting an envelope signal of a receiving modulation signal;

counting a frame delay time according to the envelope signal of the receiving modulation signal; and

transmitting a transmitting modulation signal when the frame delay time is up;

wherein the step of extracting the envelope signal of the receiving modulation signal comprises:

extracting a clock signal of the receiving modulation signal according to a first biasing voltage; and

generating a detecting signal to indicate the envelope edge of the receiving modulation signal according to a delayed clock signal of the clock signal and a second biasing voltage;

wherein the second biasing voltage or a delay time of the clock signal is adjustable.

13. The short-distance contactless communication method of claim 12 , further comprising:

determining the delay time and an offset voltage according to the receiving modulation signal;

wherein the delayed clock signal is generated by delaying the clock signal by the delay time, and the second biasing voltage is generated by offsetting the first biasing voltage by the offset voltage.

14. The short-distance contactless communication method of claim 12 , wherein the frame delay time is start to be counted when a rising edge of the envelope signal is generated.