To: ahhaha who wrote (126 ) 11/27/1998 10:44:00 AM From: Peter Ecclesine Read Replies (1) | Respond to of 626
Hi Ahhaha, Fred Dawson wrote:These concepts have to do with narrowing of laser linewidths to minimize dispersion using what is known as the "Palmer Transform" to stabilize the laser onto its optimal frequency and with new means of mixing RF signals for modulation onto the fight beam. In the modulation process, the system takes in all the various types of RF signals, whether they're digital or analog, tv or voice, IP or ATM, shaving away the upper sideband and assigning a clock sampling frequency value in the lower sideband to each signal, Gorman said. "Every signal has its own spectral output, which allows us to coherently mix them onto the beam," he said. The clock values are assigned to the beam via an external modulator, so that the four-dimensional space and time values of each photon are put to use in carrying the message. Palmer reworked the original Maxwell electromagnetic equations to come up with an exact time dialation in multiple dimensions, allowing for more signal information to be added to a given point of light than is possible with conventional two-dimensional multiplexing, Gorman explained. Because the signal input is not altered from its native format in the SilkRoad system, the technology is ideally suited for the AM signaling requirements in cable, Gorman noted. Moreover, the low attenuation and high linearity of the narrow linewidth beam allows the system to deliver AM signals at very high carrier-to-noise levels over long distances, he said. There are optical CDMA schemes around, but coherent source techniques have trouble with adding now information. How will a SR Add/Drop multiplexer Add? Does some of the original photon stream have to be unmodulated so that subsequent stations can use the photons to convey new information? It seems to me that after the femtosecond photodiode does the detecting, you need some optical way of replacing that energy, which was refractively shunted to the photodiode with another photon stream of equal energy containing new information. petere