1. A method for measuring an unknown characteristic of an optical signal incident upon a detector characterized by one or more dynamic response parameters, the method comprising:
receiving an output signal from the detector;
comparing the output signal and a computationally determined response of the detector to a known optical signal incident upon the detector, wherein the response is based on said one or more dynamic response parameters; and
determining the unknown characteristic based on results of the comparing step.
2. A method as set forth in claim 1, wherein the unknown characteristic is power.
3. A method as set forth in claim 1, wherein the unknown characteristic is energy.
4. A method as set forth in claim 1, wherein the optical signal comprises an optical pulse.
5. A method as set forth in claim 1, wherein the optical signal comprises a train of optical pulses.
6. A method as set forth in claim 1, wherein the optical signal is a laser beam.
7. A method as set forth in claim 1, wherein the detector is a pyroelectric detector.
8. A method as set forth in claim 1, wherein the detector is a thermopile detector.
9. A method as set forth in claim 1, wherein said one or more dynamic response parameters are selected from the group consisting of gain, cutoff frequency, rise time, fall time, settling time, overshoot, break frequency, natural frequency, resonant frequency, damping ratio, pole, zero, coefficient, and nonlinear term.
10. A method as set forth in claim 1, further comprising:
computationally determining, on the basis of said one or more dynamic response parameters, the computationally determined response of the detector.
11. A method as set forth in claim 1, further comprising:
retrieving from a memory the computationally determined response of the detector.
12. A method as set forth in claim 1, further comprising:
computationally determining, on the basis of said one or more dynamic response parameters, a single-pulse response of the detector to a single optical pulse having a known energy.
13. A method as set forth in claim 12, wherein the known optical signal comprises a series of optical pulses occurring at a pulse repetition rate, wherein the series of optical pulses have a known pulse width, and wherein the step of computationally determining the single-pulse response of the detector to the single optical pulse having the known energy comprises computationally convolving an impulse response of the detector with a mathematical representation of the single optical pulse, the method further comprising:
superimposing time-shifted versions of the single-pulse response, wherein the time-shift between versions equals the pulse repetition rate thereby resulting in the computationally determined response of the detector.
14. A method as set forth in claim 1, wherein the known optical signal comprises a series of optical pulses occurring at a pulse repetition rate, the method further comprising:
receiving a single-pulse response of the detector to a single optical pulse having a known energy; and
superimposing time-shifted versions of the single-pulse response, wherein the time-shift between versions equals the pulse repetition rate thereby resulting in the computationally determined response of the detector.
15. A method as set forth in claim 1, further comprising:
displaying on a display a numerical indicium representing the determined characteristic.
16. A method as set forth in claim 15, wherein the display is part of the detector.
17. A machine for measuring an unknown characteristic of an optical signal incident upon a detector characterized by one or more dynamic response parameters, the detector producing an output signal in response to the optical signal being incident upon the detector, the machine comprising:
an interface to the detector for receipt of the output signal;
a memory in which are stored data related to said one or more dynamic response parameters; and
a processor connected to the memory and to the interface, the processor being configured to compare the output signal from the detector to a calculated response of the detector to a known signal, the processor further being configured to determine, on the basis of the comparison, the unknown characteristic.
18. A machine as set forth in claim 17, wherein the unknown characteristic is power.
19. A machine as set forth in claim 17, wherein the unknown characteristic is energy.
20. A machine as set forth in claim 17, wherein the optical signal is a laser beam.
21. A machine as set forth in claim 17, wherein the detector is a pyroelectric detector.
22. A machine as set forth in claim 17, wherein the detector is a thermopile detector.
23. A machine as set forth in claim 17 further comprising:
the detector.
24. A machine as set forth in claim 17, wherein said one or more dynamic response parameters are selected from the group consisting of gain, cutoff frequency, rise time, fall time, settling time, overshoot, break frequency, natural frequency, resonant frequency, damping ratio, pole, zero, coefficient, and nonlinear term.
25. A machine as set forth in claim 17, wherein the interface comprises:
a data acquisition module connected to the detector, the data acquisition module generating digital samples of the output signal; and
a memory, connected to the data acquisition module, in which are stored the digital samples generated by the data acquisition module.
26. A machine as set forth in claim 25, wherein the data acquisition module operates at a sampling rate, and wherein the sampling rate is unrelated to said one or more dynamic response parameters.
27. A machine as set forth in claim 17, further comprising:
an input device into which a user can enter input data.
28. A machine as set forth in claim 17, further comprising:
a display on which the characteristic is displayed.
29. A non-transitory computer-readable storage device for use with a machine for measuring an unknown characteristic of an optical signal incident upon a detector characterized by one or more dynamic response parameters, the detector producing an output signal in response to the optical signal being incident upon the detector, the machine comprising an interface to the detector for receipt of the output signal, a memory in which are stored data related to said one or more dynamic response parameters, and a processor connected to the memory and to the interface, the processor operating according to program instructions embedded on the computer-readable storage device, the instructions comprising:
instructions to compare the output signal from the detector to a calculated response of the detector to a known signal; and
instructions to determine, on the basis of the comparison, the unknown characteristic.
30. A system for measuring an unknown characteristic of an optical signal incident upon a detector characterized by one or more dynamic response parameters, the system comprising:
a means for receiving an output signal from the detector;
a means for comparing the output signal and a computationally determined response of the detector to a known optical signal incident upon the detector, wherein the response is based on said one or more dynamic response parameters, the means for comparing thereby producing a comparison; and
a means for determining the unknown characteristic based on the comparison.
31. A method comprising:
receiving an output signal from an optical detector detecting one or more optical signals;
accessing a predetermined characteristic curve of detector response;
comparing the output signal from the detector to the predetermined characteristic curve of detector response; and
calculating at least one unknown characteristic of one or more optical signals based on results of the comparing step.
32. The method of claim 31, wherein the unknown characteristic is energy.
33. The method of claim 31, wherein the unknown characteristic is power.
34. The method of claim 31, wherein the accessing step comprises:
receiving the characteristic curve.
35. The method of claim 34, wherein the characteristic curve is provided by the detector.
36. The method of claim 31, wherein the output signal is received by an optical meter in communication with the detector.
37. The method of claim 36, wherein the meter compares the output signal of the detector to the characteristic curve of detector response.
38. The method of claim 37, wherein the meter calculates the characteristic curve based on data received from the detector.
39. The method of claim 38, wherein the data is selected from the group consisting of gain, cutoff frequency, rise time, fall time, settling time, overshoot, break frequency, natural frequency, resonant frequency, damping ratio, pole, zero, coefficient, and nonlinear term.
40. The method of claim 31, wherein the accessing step comprises:
calculating the characteristic curve.
41. The method of claim 40, wherein the characteristic curve is calculated based on information provided by a user.
42. The method of claim 41, wherein the information is selected from the group consisting of gain, cutoff frequency, rise time, fall time, settling time, overshoot, break frequency, natural frequency, resonant frequency, damping ratio, pole, zero, coefficient, and nonlinear term.
43. A method as set forth in claim 31, further comprising:
displaying on a display a numerical indicium representing the calculated characteristic.
44. A method as set forth in claim 43, wherein the display is part of the optical detector.
45. A machine for measuring an unknown characteristic of one or more optical pulses incident upon an optical detector characterized by one or more dynamic response parameters, the pulses having a known pulse repetition rate, the machine comprising:
an input connection for receiving an output signal from the detector, the output signal resulting from the pulses being incident upon the detector;
a memory in which are stored data related to said one or more dynamic response parameters; and
a processor operatively connected to the memory and to the input connection, the processor being configured to calculate, on the basis of the stored data, a response of the detector to a train of optical pulses having the known pulse repetition rate and a known energy, the processor being further configured to compare the output signal from the detector to the calculated response and to measure the unknown characteristic on the basis of that comparison.
46. A machine as set forth in claim 45, wherein the pulse repetition rate is known a priori.
47. A machine as set forth in claim 45, further comprising:
a pulse rate measuring circuit to determine the pulse repetition rate.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A DSSS and OFDM two-way waiting reception method in a wireless LAN apparatus supporting DSSS and OFDM, the DSSS and OFDM two-way waiting reception method comprising the steps of:
(a) maintaining a two-way waiting state if none of an RSSI trigger, an OFDM search trigger, and a DSSS search trigger is generated;
(b) making a transition to an RSSI-activated OFDM reception state if the RSSI trigger is generated in the two-way waiting state;
(c) making a transition to a DSSS reception state if an OFDM synchronization loss trigger is generated in the RSSI-activated OFDM reception state;
(d) making a transition to an OFDM search-activated OFDM reception state if the OFDM search trigger is generated in the two-way waiting state;
(e) making a transition to the DSSS reception state if the DSSS search trigger is generated and the OFDM synchronization loss trigger is generated in the OFDM search-activated OFDM reception state; and
(f) making a transition to the DSSS reception state if the DSSS search trigger is generated in the two-way waiting state.
2. The DSSS and OFDM two-way waiting reception method as claimed in claim 1, further comprising the steps of:
(g) maintaining the RSSI-activated OFDM reception state during OFDM reception after the transition to the RSSI-activated OFDM reception state;
(h) maintaining the OFDM search-activated OFDM reception state during OFDM reception after the transition to the OFDM search-activated OFDM reception state; and
(i) maintaining the DSSS reception state during DSSS reception after the transition to the DSSS reception state.
3. The DSSS and OFDM two-way waiting reception method as claimed in claim 1, further comprising the steps of:
(g) making a transition to the two-way waiting state if an OFDM end trigger is generated after the transition to the RSSI-activated OFDM reception state;
(h) making a transition to the two-way waiting state if one of the OFDM end trigger and the OFDM synchronization loss trigger is generated after the transition to the OFDM search-activated OFDM reception state; and
(i) making a transition to the two-way waiting state if a DSSS end trigger is generated after the transition to the DSSS reception state.
4. A wireless LAN apparatus supporting DSSS and OFDM, comprising:
an RF interface part configured to provide interface with an RF part and to control an operation of each of a DSSS part to perform DSSS demodulation and an OFDM part to perform OFDM demodulation,
wherein the RF interface part causes a two-way waiting state to be maintained if none of an RSSI trigger, an OFDM search trigger, and a DSSS search trigger is generated;
causes a transition to an RSSI-activated OFDM reception state if the RSSI trigger is generated in the two-way waiting state;
causes a transition to a DSSS reception state if an OFDM synchronization loss trigger is generated in the RSSI-activated OFDM reception state;
causes a transition to an OFDM search-activated OFDM reception state if the OFDM search trigger is generated in the two-way waiting state;
causes a transition to the DSSS reception state if the DSSS search trigger is generated and the OFDM synchronization loss trigger is generated in the OFDM search-activated OFDM reception state; and
causes a transition to the DSSS reception state if the DSSS search trigger is generated in the two-way waiting state.
5. The wireless LAN apparatus as claimed in claim 4, wherein the RF interface part causes the RSSI-activated OFDM reception state to be maintained during OFDM reception after the transition to the RSSI-activated OFDM reception state;
causes the OFDM search-activated OFDM reception state to be maintained during OFDM reception after the transition to the OFDM search-activated OFDM reception state; and
causes the DSSS reception state to be maintained during DSSS reception after the transition to the DSSS reception state.
6. The wireless LAN apparatus as claimed in claim 4, wherein the RF interface part causes a transition to the two-way waiting state if an OFDM end trigger is generated after the transition to the RSSI-activated OFDM reception state;
causes a transition to the two-way waiting state if one of the OFDM end trigger and the OFDM synchronization loss trigger is generated after the transition to the OFDM search-activated OFDM reception state; and
causes a transition to the two-way waiting state if a DSSS end trigger is generated after the transition to the DSSS reception state.
7. A DSSS and OFDM two-way waiting reception method in a wireless LAN apparatus supporting DSSS and OFDM, the DSSS and OFDM two-way waiting reception method comprising the steps of:
(a) performing each of DSSS correlation detection and OFDM correlation detection so as to determine whether a received signal is a DSSS signal or an OFDM signal;
(b) performing OFDM reception as a result of generation of an OFDM search trigger because of detection of OFDM correlation;
(c) interrupting said step (b) and switching to DSSS reception on generation of a DSSS search trigger due to detection of DSSS correlation in said step (b); and
(d) performing the DSSS reception.
8. The DSSS and OFDM two-way waiting reception method as claimed in claim 7, wherein a threshold level for detecting the DSSS correlation is higher in said step (a) than in said step (b).
9. The DSSS and OFDM two-way waiting reception method as claimed in claim 8, wherein the threshold level for detecting the DSSS correlation is higher in said step (b) than in said step (d).
10. The DSSS and OFDM two-way waiting reception method as claimed in claim 7, wherein a threshold level for detecting the DSSS correlation is variable based on a level of the received signal.
11. A wireless LAN apparatus supporting DSSS and OFDM, comprising:
a correlation detection part configured to perform each of DSSS correlation detection and OFDM correlation detection so as to determine whether a received signal is a DSSS signal or an OFDM signal;
an OFDM reception part configured to perform OFDM reception; and
a DSSS reception part configured to perform DSSS reception,
wherein the OFDM reception in the OFDM reception part is interrupted and switched to the DSSS reception in the DSSS reception part on generation of a DSSS search trigger due to detection of DSSS correlation in the correlation detection part during the OFDM reception in the OFDM reception part.
12. The wireless LAN apparatus as claimed in claim 11, wherein the correlation detection part has a variable threshold level for detecting the DSSS correlation.