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At a base station 2, a CDMA received signal coming in through an antenna 4 is fed to a radio frequency unit (RFU) or high frequency unit 6. The RFU 6 demodulates a baseband signal BB from a signal RF and delivers the signal BB to an analog-to-digital converter (A/D) 8. The resulting digital signal o

At a base station 2, a CDMA received signal coming in through an antenna 4 is fed to a radio frequency unit (RFU) or high frequency unit 6. The RFU 6 demodulates a baseband signal BB from a signal RF and delivers the signal BB to an analog-to-digital converter (A/D) 8. The resulting digital signal output from the A/D 8 is input to a hybrid interference canceller (HIC) 12 as a received signal Rx Data 10. The HIC 12 divides users into two groups and assigns one combination of a parallel interference canceller and a serial interference canceller to each group. The HIC 12 cancels interference contained in the received signal Rx Data 10 for thereby estimating symbols particular to a plurality of users.

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At a base station 2, a CDMA received signal coming in through an antenna 4 is fed to a radio frequency unit (RFU) or high frequency unit 6. The RFU 6 demodulates a baseband signal BB from a signal RF and delivers the signal BB to an analog-to-digital converter (A/D) 8. The resulting digital signal o

At a base station 2, a CDMA received signal coming in through an antenna 4 is fed to a radio frequency unit (RFU) or high frequency unit 6. The RFU 6 demodulates a baseband signal BB from a signal RF and delivers the signal BB to an analog-to-digital converter (A/D) 8. The resulting digital signal output from the A/D 8 is input to a hybrid interference canceller (HIC) 12 as a received signal Rx Data 10. The HIC 12 divides users into two groups and assigns one combination of a parallel interference canceller and a serial interference canceller to each group. The HIC 12 cancels interference contained in the received signal Rx Data 10 for thereby estimating symbols particular to a plurality of users. st and second excitation signals are combined using a transformer. 6. The method of claim 5, further comprising amplifying a voltage amplitude of one of the first or second excitation signals via the transformer. 7. The method of claim 1, further comprising: detecting the first and second intensity modulations of the laser output to produce a composite intensity modulation feedback signal; filtering out a substantial portion of the composite intensity modulation feedback signal pertaining to the portion of the composite signal due to SBS suppression to produced a filtered feedback signal; and employing the filtered feedback signal to tune the laser. 8. The method of claim 7, wherein the intensity modulations of the laser output are detected using a photo-electric sensor. 9. The method of claim 7, wherein the intensity modulations of the laser output are detected by monitoring a change in an electrical characteristic of a gain medium employed by the laser. 10. The method of claim 7, wherein the laser is tuned by adjusting an overall length of the laser cavity. 11. A laser comprising: a base; a gain medium operatively coupled to the base, having front and rear facets, to produce an optical emission in response to an electrical input; a reflective element, operatively coupled to the base, to form a laser cavity having endpoints defined by the front facet of the gain medium and a face of the reflective element; an optical path length adjustment element operatively coupled to the base; and a controller to generate an electrical input comprising first and second excitation signals to the optical path length adjustment element to produce first and second modulations of the overall optical path length of the laser cavity, which induce respective first and second wavelength and intensity modulations in an output of the laser about respective first and second frequencies, the first wavelength and intensity modulation to produce a wavelength locking feedback signal employed by the controller to lock the laser output to a selected channel, the second wavelength and intensity modulation to suppress stimulated Brillouin scattering. 12. The laser of claim 11, further comprising: a detector, to produce an output signal corresponding to the first and second intensity modulations in the laser output; and a filter, to receive the detector output signal as an input and substantially filter out the second intensity modulation to produce a filtered output signal that is received as a tuning feedback input signal by the controller. 13. The apparatus of claim 12, further comprising: at least one thermoelectric element, thermally coupled to the base; and a tuning servo mechanism provided by the controller that provides fine tuning adjustment to a frequency of the laser output by adjusting the temperature of the base via an electrical input to said at least one thermoelectric element. 14. The laser of claim 12, wherein the detector comprises a photo-electric sensor, and the laser further includes a beam splitter disposed in an optical path of the output of the laser to split off a portion of the output and direct the split-off portion toward the photo-electric sensor. 15. The laser of claim 12, wherein the gain medium comprises a diode laser, and the detector comprises a voltage detector that detects a voltage difference across a diode junction of the laser diode. 16. The laser of claim 11, wherein the optical path length adjustment element comprises an optical element disposed in the laser cavity made of a material that changes its index of refraction in response to an electrical input. 17. The laser of claim 16, wherein the reflective element is coupled to a rear face of the optical path length adjustment element. 18. The laser of claim 11, wherein the optical path length adjustment element comprises a piezoelectric element operatively coupled to the reflective element. 19. The laser of claim 11, wherein the optical path l ength adjustment element comprises a Micro-Electro-Mechanical Systems (MEMS) element coupled to the base and the reflective element and responsive to an electric input to cause a displacement in the location of the reflective element. 20. The laser of claim 11, wherein the controller generates respective first and second excitation signals to induce the first and second modulations in the overall optical path length of the laser cavity, said first and second excitation signals being independently controllable. 21. The laser of claim 11, wherein the gain medium includes a gain section and a phase control section via which a change in the optical path length of the gain medium may be adjusted in response to an electrical input, said phase control section comprising the optical path length adjustment element. 22. The laser of claim 11, wherein the controller generates respective first and second excitation signals to induce the first and second modulations in the overall optical path length of the laser cavity, further comprising a signal combiner to receive the first and second excitation signals as in input and output a combined excitation signal that is used to drive the optical path length adjustment element. 23. The laser of claim 22, wherein the combiner comprises a transformer. 24. The laser of claim 23, wherein the transformer is further employed to amplify the second excitation signal. 25. A laser comprising: a gain medium to generate an optical emission; first and second reflective elements, defining a laser cavity; first means for adjusting an overall optical path length of the laser cavity; and control means for generating a drive signal to the means for adjusting the overall optical path length of the laser cavity to cause first and second modulations in the overall optical path length of the laser cavity to induce first and second wavelength and intensity modulations in an output of the laser about respective first and second frequencies, the first wavelenght and intensity modulation to produce a wavelength locking feedback signal employed by the controller to lock the laser output to a selected channel, the second wavelength and intensity modulation to suppress stimulated Brillouin scattering. 26. The laser of claim 25, wherein the second intensity modulation has an amplitude at least one order of magnitude greater than the first intensity modulation. 27. The laser of claim 25, further comprising second means for adjusting the overall optical path length of the laser cavity, said second means employed for fine tuning an output frequency of the laser output in response to a feedback signal derived from the first intensity modulation. 28. The laser of claim 27, further comprising: detection means for providing a feedback signal indicative of the first and second intensity modulations; and filtering means for filtering the feedback signal such that the second intensity modulation portion of the feedback signal is substantially attenuated. 29. The laser of claim 25, wherein the second intensity modulation is about a frequency selected to suppress stimulated Brillouin scattering in an optical fiber. between the first packet's arrival and each subsequent packet's arrival as measured by the receiver clock; defining a feasible region of solution for an estimate α of the ratio between the speed of the sender clock and the speed of the receiver clock and for an estimate β of the end-to-end delay of the first packet consistent with the receiver clock, wherein the feasible region is defined by the following condition: and minimizing the vertical distance between the line and all delay measurements according to the formula 2. A method of claim 1, further comprising: eliminating the requirement that certain constraints be examined in processing by using the data point for the cumulative minimum delay as the minimum delay between the sender clock and the receiver clock for a subsequent packet. 3. A method of claim 1, further comprising: for a data set of transmissions of different packet sizes, determining the mode packet size for the set of transmissions and using only measurements of transmissions of packets of the mode packet size in defining the feasible region and minimizing the distance between the line and the delay measurements. 4. A method of estimating clock skew from network delay measurements, comprising: measuring the end-to-end delay for a plurality of transmissions over a plurality of time periods between a sender and a receiver to obtain a plurality of minimum delay data points; defining a feasible region of solution as the set of points for each time period that is lower than the measured delay for each time period; and fitting a line that is the closest line to the data points representing the minimum delay but that is within the feasible region of solution. 5. A method of claim 4, wherein fitting the line comprises minimizing the sum of the distances between the line and the minimum delay data points. 6. A method of claim 4, further comprising: selecting a data set consisting of packets of a mode packet size. 7. A method of claim 4, further comprising: using the data point for the cumulative minimum delay as the minimum delay between the sender clock and the receiver clock for a subsequent packet. 8. A method of claim 4, further comprising: correcting a measurement to account for clock skew. 9. A method of estimating clock skew from network delay measurements, comprising: measuring the end-to-end delay for a plurality of data packet transmissions over a plurality of time periods between a sender and a receiver to obtain a data set; determining a plurality of minimum delay data points consisting of the lowest delay for each of the plurality of time periods; defining a feasible region of solution as the set of points for each time period that is lower than the measured delay for each time period; fitting a line that is the closest line to the data points representing the minimum delay but that is within the feasible region of solution, wherein fitting the line comprises minimizing the sum of the distances between the line and all the data points in the data set; eliminating the requirement that certain constraints be examined in processing by using the data point for the immediately prior packet as the minimum delay between the sender clock and the receiver clock for a subsequent packet; and for a data set of transmissions of different packet sizes, determining the mode packet size for the set of transmissions and using only measurements of transmissions of packets of the mode packet size in defining the feasible region and minimizing the distance between the line and the delay measurements. 10. A system for correcting clock skew, comprising: a network for sending data packets between a sender device and a receiver device, the sender device having a sender clock and the receiver device having a receiver clock, a processor for processing measurements consisting of the time duration between a first packet's departure and each subsequent packet's departure consiste nt with the time measured by the sender clock and for obtaining a calculated set of delay measurements consisting of the amounts determined by subtracting the time duration between the first packet's departure and each subsequent packet's departure as measured by the sender clock from the time duration between the first packet's arrival and each subsequent packet's arrival as measured by the receiver clock, wherein the processor defines a feasible region of solution for an estimate α of the ratio between the speed of the sender clock and the speed of the receiver clock and for an estimate β of the end-to-end delay of the first packet consistent with the receiver clock, wherein the feasible region is defined by the following condition: and wherein the processor minimizes the distance between the line and all delay measurements according to the formula 11. A system of claim 10, wherein the processor eliminates the requirement that certain constraints be examined in processing by using the data point for cumulative minimum delay as the minimum delay between the sender clock and the receiver clock for a subsequent packet. 12. A system of claim 10, wherein the processor, for a data set of transmissions of different packet sizes, determines the mode packet size for the set of transmissions and uses only measurements of transmissions of packets of the mode packet size in defining the feasible region and minimizing the distance between the line and the delay measurements. 13. A system for correcting clock skew, comprising: means for transmitting data packets between a sender device and a receiver device, the sender device having a sender clock and the receiver device having a receiver clock; means for processing measurements consisting of the time duration between a first packet's departure and each subsequent packet's departure consistent with the time measured by the sender clock and for obtaining a calculated set of delay measurements of the time duration between departure of each packet from the sender device and arrival of the packet at the receiver device; means for defining a feasible region of solution as the set of points for each time duration that is lower than the measured delay for each time duration; and means for fitting a line that is the closest line to the data points representing the minimum delay but that is that is within the feasible region of solution. 14. A method of providing timing recovery of video transmissions, comprising: estimating the skew between a sender clock and a receiver clock on a network, the step of estimating the skew comprising for a set of packets sent over a network, obtaining a set of measurements consisting of the time duration between a first packet's departure and each subsequent packet's departure consistent with the time measured by a sender clock; obtaining a calculated set of delay measurements consisting of the amounts determined by subtracting the time duration between the first packet's departure and each subsequent packet's departure as measured by the sender clock from the time duration between the first packet's arrival and each subsequent packet's arrival as measured by the receiver clock; defining a feasible region of solution for an estimate α of the ratio between the speed of the sender clock and the speed of the receiver clock and for an estimate β of the end-to-end delay of the first packet consistent with the receiver clock, wherein the feasible region is defined by the following condition: and minimizing the vertical distance between the line and all delay measurements according to the formula and adjusting the timing of a packet of video data to reflect the estimated skew. 15. A method of claim 14, wherein the video data is MPEG-2 video data. 16. A method of providing a multi-user application, comprising: providing a host system with an application environment; providing a plurality of user systems connected to the host system via a communication link; estimating clock skew among the host system and the user systems from network delay measurements, wherein the step of estimating clock skew comprises measuring the end-to-end delay for a plurality of transmissions over a plurality of time periods between a sender and a receiver to obtain a plurality of minimum delay data points; and fitting a line that is the closest line to the data points representing the minimum delay but that is less than the minimum delay for each transmission period; and adjusting the timing of the application to account for the estimated clock skew. 17. A method of claim 16, wherein fitting a line comprises: defining a feasible region of solution for an estimate α of the ratio between the speed of the sender clock and the speed of the receiver clock and for an estimate β of the end-to-end delay of the first packet consistent with the receiver clock, wherein the feasible region is defined by the following condition: and minimizing the vertical distance between the line and all delay measurements according to the formula 18. A method of claim 16, wherein the application is a computer game. 19. A method of claim 16, wherein the application is a virtual reality application. 20. A method of claim 16, wherein the application is a real-time simulation. 21. A method of claim 16, wherein the application is a combat simulation. 22. A method of claim 16, wherein the application is a flight simulation. 23. A method of claim 16, wherein the application is a driving simulation. 24. A method of claim 16, wherein the application is an audio application. ype surface light emitting semiconductor laser device according to claim 3, wherein an insulating film is provided in a region at which the protective film is not formed or on a contact layer, and a region corresponding to the contact hole at which neither the insulating film nor the protective film is formed is covered with a contact electrode. 5. A vertical resonator type surface light emitting semiconductor laser device according to claim 1, wherein a film thickness of the protective film satisfies the following condition: d=(λ/2)*(N/n) wherein d denotes the film thickness of the protective film, λ denotes a wavelength of the laser light, n denotes a reflectance of said protective film, and N is a nonnegative integer. 6. A vertical resonator type surface light emitting semiconductor layer device according to claim 3, wherein a protective film formed on said contact layer includes a substantially flat region and an inclined region at a side free from contact with said semiconductor multi-layered film reflection mirror or contact layer, and an opening of the contact electrode is formed at an upper surface of the substantially flat region or at a lower portion of the inclined region as viewed from a thickness direction of the protective film, and a film thickness of the protective film in the substantially flat region satisfies the following condition: d=(λ/2)*(N/n) wherein d denotes the film thickness of the protective film, λ denotes a wavelength of the laser light, n denotes a reflectance of said protective film, and N is a nonnegative integer. 7. A vertical resonator type surface light emitting semiconductor laser device according to claim 1, wherein the protective film is selected from among an SiO2film, SiOxNyfilm, a SiNxfilm, and InxSnyOzfilm. 8. A method of fabricating a vertical resonator type surface light emitting semiconductor laser device comprising the steps of: forming, in order on a semiconductor substrate, a first conductivity type semiconductor multi-layered film reflection mirror, an active layer, a semiconductor layer to be oxidized, a second conductivity type semiconductor multi-layered film reflection mirror, a second conductivity type contact layer, and a contact electrode having an opening for emitting laser light; forming a protective film for protecting the opening of the contact electrode from damage due to fabrication after forming said contact electrode, a surface area of said protective film being greater than an area of the opening of the contact electrode and smaller than an area of the contact electrode; etching the semiconductor layer to be oxidized to expose an edge thereof; oxidizing the semiconductor layer to be oxidized from the edge by steam to form a emitting port; laminating an insulating film; forming a contact hole in said insulating film so as to include therein the protective film positioned in said opening, a size of said contact hole being smaller than an area of said contact electrode, and said contact hole connecting said wiring electrode and said contact electrode; and forming a electrode having a conductivity type that is different from that of the contact electrode. 9. A vertical resonator type surface light emitting semiconductor laser device according to claim 3, wherein said emitting port is formed by steam oxidation. 10. A vertical resonator type surface light emitting semiconductor laser device according to claim 1, wherein the protective film is one of an SiO2film and an SiOxNyfilm, and the insulating film is an SiNxfilm. 11. A vertical resonator type surface light emitting semiconductor laser device according to claim 3, wherein the protective film is one of an SiO2film and an SiOxNyfilm, and the insulating film is an SiNxfilm.