摘要:
A technique has been developed to fabricate micro- or nanopumps based on porous alumina thin films. The main body of the nanopump consists of a porous alumina thin film (containing nano-sized channels of about 40-300 nm in diameter) with conductive surfaces (e.g. Au coating layers) on both sides of the film. Through the fabrication of nanochannels in (the alumina films) and the subsequent annealing and surface activation processes, high-efficiency micro- or nanopumps can be made. The nanofluidic flow through the nanochannels of the alumina thin films is driven by an electric field with no moving parts. The flow rate (up to 50 millilitres/(min·cm2)) of water through the alumina thin film can be continuously tuned through the intensity of the electric field, i.e., the DC electric potential applied across the nanochannels.
摘要:
A technique has been developed to fabricate micro- or nanopumps based on porous alumina thin films. The main body of the nanopump consists of a porous alumina thin film (containing nano-sized channels of about 40-300 nm in diameter) with conductive surfaces (e.g. Au coating layers) on both sides of the film. Through the fabrication of nanochannels in (the alumina films) and the subsequent annealing and surface activation processes, high-efficiency micro- or nanopumps can be made. The nanofluidic flow through the nanochannels of the alumina thin films is driven by an electric field with no moving parts. The flow rate (up to 50 millilitres/(min·cm2)) of water through the alumina thin film can be continuously tuned through the intensity of the electric field, i.e., the DC electric potential applied across the nanochannels.
摘要:
In a method for generating a signal quality indicator, a correlation signal is generated from a received signal and a spreading sequence. A magnitude signal is generated from the correlation signal. A time-domain averaged signal is generated based on the magnitude signal and at least a first time delayed version of the magnitude signal delayed by at least one symbol period. A peak-to-average signal is generated based on the time-domain averaged signal.
摘要:
A system including an activity sensing module to sense RF activity in first and second sub-channels of a communication channel of a first wireless network. N adjacent channel interference (ACI) filter modules arranged in parallel receive signals from N antennas, respectively, filter out signals in channels adjacent to the communication channel, and generate N filtered signals, respectively, where N>2. The activity sensing module generates control signals based on the N filtered signals. A channel identification module processes the control signals, and determines that both of the first and second sub-channels are available when the RF activity originating from a second wireless network is not present in both of the first and second sub-channels, and that the first sub-channel is available when the RF activity originating from the second wireless network is present only in the second sub-channel and is less than or equal to a predetermined threshold.
摘要:
In detecting a signal, angle information is generated based on a complex signal having a periodic portion. An autocorrelation signal is generated based on the angle information and not based on magnitude information associated with the complex signal. The periodic portion is detected based on the autocorrelation signal.
摘要:
In a method for generating a signal quality indicator, a correlation signal is generated from a received signal and a spreading sequence. A magnitude signal is generated from the correlation signal. A time-domain averaged signal is generated based on the magnitude signal and at least a first time delayed version of the magnitude signal delayed by at least one symbol period. A peak-to-average signal is generated based on the time-domain averaged signal.
摘要:
An early-late gate based ADC timing approach is described for performing early-late gate timing recovery despite the presence of multipath signal distortion. Multipath conditions may severely distort Barker correlator magnitudes generated for taps within two taps of a determined bit synchronization time. Exemplary embodiments of the described approach may combine Barker correlator magnitudes for several receive chains to calculate the timing error correction corresponding to a difference of early and late taps. The approach may be used to increase the size and stability of Barker correlator magnitudes generated for taps far away from a determined bit synchronization time. Such embodiments allow early-late differences to be generated using combined Barker correlator magnitudes generated at taps that are two or more chips from a determined bit synchronization time, thereby avoiding multipath distortion that may distort Barker correlator magnitudes generated within two or more chips from the determined bit synchronization time.
摘要:
A wireless networking receiver with digital antenna switching selects an antenna with an 802.11b signal based on a signal metric, such as the highest signal quality or highest peak amplitude. In one embodiment, the receiver comprises a plurality of antennas that may each receive one of a plurality of RF signals conforming to the IEEE 802.11b standard. The receiver may have multiple antennas for use with the IEEE 802.11n standard, but may receive signals conforming to the 802.11b standard. The receiver also comprises a carrier sense circuit configured to calculate a signal metric for each of the signals and further configured to generate a selection signal signifying one of the signals, based on the signal metric. The receiver further comprises a multiplexer configured to output one of the signals, based on the selection signal. In another embodiment, a wireless networking receiver comprises signal receiving means, carrier sensing means for calculating and selecting a signal based on a signal metric, and multiplexer means to output the signal. A related method is also disclosed. Other embodiments are provided, and each of the embodiments described herein can be used alone or in combination with one another.
摘要:
Systems, circuits and methods for phase-shifting pulse width modulated signal generation are disclosed. In some embodiments, a phase-shifting pulse width modulation circuit is configured to output pulses based on an input pulse width modulated signal. The pulses are staggered relative to one another, and can be received by a light-emitting diode driver for driving a light-emitting diode string at one or more time periods. The phase-shifting pulse width modulation circuit can include a counter-based programmable delay subcircuit consisting of two counter-based programmable delay blocks.
摘要:
In detecting a signal, angle information is generated based on a complex signal having a periodic portion. An autocorrelation signal is generated based on the angle information and not based on magnitude information associated with the complex signal. The periodic portion is detected based on the autocorrelation signal.