摘要:
This patent describes a method and system which overcomes the LO-leakage problem of direct conversion and similar RF transmitters. To solve this problem a virtual LO™ signal is generated within the baseband which is tuned to the incoming RF signal. The virtual local oscillator (VLO) signal is constructed using signals that do not contain a significant amount of power (or no power at all) at the wanted output RF frequency. Any errors is generating the virtual LO signal are minimized using a closed loop correction scheme.
摘要:
This patent describes a method and system which overcomes the LO-leakage problem of direct conversion and similar RF transmitters and receivers. To solve this problem a virtual LO™ signal is generated which emulates mixing with a local oscillator (LO) signal. However, the virtual local oscillator (VLO) signal is constructed using signals that do not contain a significant amount of power (or no power at all) at the wanted output RF frequency, so there is no LO component to leak to the output. The invention also does not require sophisticated filters or large capacitors as other designs in the art, so it is fully integratable.
摘要:
This patent describes a method and system which overcomes the LO-leakage problem during modulation and demodulation, common to direct conversion and similar RF transmitters and receivers. This problem is solved using a virtual local oscillator (VLO™) signal which emulates mixing with a local oscillators (LO) signal. The VLO signal is constructed using complementary mixing signals that suppress mixing power in the bandwidth of the input signal, and within the bandwidth of the output frequency. Specifically, mixing is done in two or more stages, using time-varying mixing signals φ1 and φ2 which satisfy the following criteria: φ1*φ2 having significant power at the frequency of the LO being emulated, one of φ1 and φ2 having minimal power around the frequency of the output signal y(t), and the other of φ1 and φ2 having minimal power around the center frequency, fRF, of the input signal x(t).
摘要:
An antenna includes an antenna base having a first optically cured resin body and a conductive layer thereon. In addition, the antenna also has at least one feed line constructed from an electrically conductive material. Moreover, a feed line retainer including a second optically cured resin body and having at least one recess therein carries the at least one feed line. The feed line retainer is positioned within the antenna base such that the at least one feed line does not contact the electrically conductive layer on the antenna base.
摘要:
The tubular slot-mode antenna includes an array of slot antenna units carried by a tubular substrate, e.g. a cylindrical substrate, and each slot antenna unit having a pair of patch antenna elements arranged in laterally spaced apart relation about at least one central feed position. Adjacent patch antenna elements of adjacent slot-mode antenna units have respective spaced apart edge portions with predetermined shapes and relative positioning to provide increased capacitive coupling therebetween. The array of slot-mode antenna units may define a plurality of ring-shaped slots coaxial with an axis of the tubular substrate, and a feed arrangement may be coupled thereto to operate the array of slot-mode antenna units in an endfire mode.
摘要:
The tubular slot-mode antenna includes an array of slot antenna units carried by a tubular substrate, e.g. a cylindrical substrate, and each slot antenna unit having a pair of patch antenna elements arranged in laterally spaced apart relation about at least one central feed position. Adjacent patch antenna elements of adjacent slot-mode antenna units have respective spaced apart edge portions with predetermined shapes and relative positioning to provide increased capacitive coupling therebetween. The array of slot-mode antenna units may define a plurality of ring-shaped slots coaxial with an axis of the tubular substrate, and a feed arrangement may be coupled thereto to operate the array of slot-mode antenna units in an endfire mode.
摘要:
A dual polarization antenna includes a substantially pyramidal configured substrate having opposing walls. An antenna element is carried at each wall such that opposing pairs of antenna elements define respective antenna dipoles and provide dual polarization.
摘要:
A dual polarization antenna includes a substantially pyramidal configured substrate having opposing walls. An antenna element is carried at each wall such that opposing pairs of antenna elements define respective antenna dipoles and provide dual polarization.
摘要:
Valve operator having a weighted powering assembly that is substantially supported and balanced on a generally upright elongated key that drivingly engages a rotatable valve nut.