Abstract:
PROBLEM TO BE SOLVED: To provide the transconductance filter in which a stable operation is continued while a die area is reduced and power consumption is decreased. SOLUTION: The transconductance filter 200 is made up of multi-stage conductors 110, 120, 130 each having inputs and an output and switches 260, 265, 270 coupled between each output and a voltage source. Each switch responds to a control signal 275 in terms of the operation to directly connect the voltage source and the output of each transconductor or disconnect them before a point of time when at least the filter filters an input voltage signal. The voltage of the voltage source is within a prescribed input voltage range of the transconductor that is specified by a range of the transconductance of the transconductor being nearly constant and positive.
Abstract:
A transconductance filter (200) comprises multiple stages of a transconductor (110,120,130) having an input and an output, and a switch (260,265,270) coupled between the output and the voltage source. The switch is operatively responsive to the control signal for coupling and decoupling the voltage source directly to the output of the transconductor at least prior to the time the filter is required to filter the input voltage signal. The voltage source is within a predetermined input voltage range of the transconductor defined by a region in which a transconductance of the transconductor is substantially constant and positive.
Abstract:
A transconductance-capacitor filter comprises multiple stages of a transconductor 210,220,230 having an input and an output, and a switch 260,265,270 coupled between the output and a voltage source VAG. The switch is operatively responsive to a control signal 275 for coupling and decoupling the voltage source directly to the output of the transconductor at least prior to the time the filter is required to filter an input voltage signal 205. The voltage source is within a predetermined input voltage range of the transconductor defined by a region in which a transconductance of the transconductor is substantially constant and positive.
Abstract:
The device and method provide active-addressing drive signals foran LCD by utilizing an efficient implementation of Walsh functions. By implementation of a technique for determining fast Walsh transformations, real time active-addressing of the drive signals are provided by determining random access memory (RAM) addresses for sending preselected portions of the digital image data (PPDIDs) to a plurality of RAMs (106, 108, 110), and controlling simultaneous parallel input/output of data to/from the RAMs and a fast Walsh transform circuit (FWTC 102) such that fast Walsh transform (FWTs) are performed on input digital image data. For example, active-addressing drive signals for one-half of a 240 by 640 column sized LCD may be determined in real time. Thus, two of the devices of the present invention may be utilized to provide a system for real time active-addressing for a typical visual graphics array (VGA) LCD.
Abstract:
In certain embodiments of a cognitive radio (100), a method of establishing operational policies, involves determining that a new policy decision should be made; requesting a policy decision from an authority having more computing power than the cognitive radio; receiving the policy decision from the authority; and implementing the policy decision in the cognitive radio. Other embodiments may incorporate more, fewer or other elements.
Abstract:
Performance of a radio device is optimized by estimating if the device is inside a building. One or more sensors on the radio device are use to measure an environmental quantities relating to the environment of the radio device. The likelihood of the radio device being inside a building is inferred from these measurements. The operation of the radio device then is controlled accordingly. For example, if the radio device is determined to be inside a building, a low operating frequency may be selected for the radio device if a wide area network connection is required, while a high operating frequency may be selected if a local connection is required. An environmental quantity may be, for example, a satellite signal, ambient light, temperature, RF energy, or the response to a test signal emitted by the radio device.