摘要:
A signal canceller includes a dual-drive electro-optic modulator having separate first and second electrical inputs. The first electrical input is coupled to a first portion of a first signal and the second electrical input is coupled to a second signal and to a second portion of the first signal. A laser generates an optical beam that propagates from the optical input to an optical output of the electro-optic modulator. The dual-drive electro-optic modulator modulates the optical beam with the first and second portions of the first signal and with the second signal. The modulation cancels at least some the first signal and generates a modulation signal with reduced first signal modulation component.
摘要:
An electromagnetic reflector includes an antenna that receives an incoming signal and that transmits an outgoing signal. A three-port device, such as a circulator, has a first port electromagnetically coupled to the antenna. An RF circuit has an input that is electromagnetically coupled to the second port of the three-port device and an output that is electromagnetically coupled to the third port of the three-port device. The RF circuit changes at least one of a gain and a phase of the incoming signal to generate a desired outgoing signal that passes through the three-port device to the antenna.
摘要:
An electromagnetic reflector includes an antenna that receives an incoming signal and that transmits an outgoing signal. A three-port device, such as a circulator, has a first port electromagnetically coupled to the antenna. An RF circuit has an input that is electromagnetically coupled to the second port of the three-port device and an output that is electromagnetically coupled to the third port of the three-port device. The RF circuit changes at least one of a gain and a phase of the incoming signal to generate a desired outgoing signal that passes through the three-port device to the antenna.
摘要:
A signal canceller includes a dual-drive electro-optic modulator having separate first and second electrical inputs. The first electrical input is coupled to a first portion of a first signal and the second electrical input is coupled to a second signal and to a second portion of the first signal. A laser generates an optical beam that propagates from the optical input to an optical output of the electro-optic modulator. The dual-drive electro-optic modulator modulates the optical beam with the first and second portions of the first signal and with the second signal. The modulation cancels at least some the first signal and generates a modulation signal with reduced first signal modulation component.
摘要:
An electromagnetic reflector includes an antenna that receives an incoming signal and that transmits an outgoing signal. A three-port device, such as a circulator, has a first port electromagnetically coupled to the antenna. An RF circuit has an input that is electromagnetically coupled to the second port of the three-port device and an output that is electromagnetically coupled to the third port of the three-port device. The RF circuit changes at least one of a gain and a phase of the incoming signal to generate a desired outgoing signal that passes through the three-port device to the antenna.
摘要:
A signal canceller includes a dual-drive electro-optic modulator having separate first and second electrical inputs. The first electrical input is coupled to a first portion of a first signal and the second electrical input is coupled to a second signal and to a second portion of the first signal. A laser generates an optical beam that propagates from the optical input to an optical output of the electro-optic modulator. The dual-drive electro-optic modulator modulates the optical beam with the first and second portions of the first signal and with the second signal. The modulation cancels at least some the first signal and generates a modulation signal with reduced first signal modulation component.
摘要:
A chaotic transmitter (100) operates according to preselected chaotic protocols, such as a set of Lorenz equations. Modulation is accomplished by modifying a predetermined parameter of the set of chaotic Lorenz equations with a message signal, thereby producing a spread spectrum chaotic transmitted signal. A corresponding receiver (200) reconstructs a synchronizing drive signal, which is used by a demodulator (412) of the receiver (200) to detect the message signal.
摘要:
A radar system coherently combines signals from independent upper- and lower-sub-band radars, mutually coheres the sub-band radar signals, and performs model fitting and parameter estimation to obtain ultra-wideband data signatures from a target. Signal processing models are used to compensate for potential lack of mutual coherence between the various sub-bands. An ultra-wideband signal model is fitted to the sparse sub-band measurements to accurately characterize ultra-wideband target scattering and provide for meaningful interpolations or extrapolations outside of the measurement sub-bands.