A method according to one embodiment for mitigating radio frequency interference by identifying system clocks, identifying active radio channels, measuring clock harmonics in or near the active radio channels, determining potential interference occurring if the clocks were moved to new fundamental frequencies, and shifting clock fundamental frequencies to reduce interference to the active radio channels based on existing interference and the potential interference of a plurality of new fundamental frequencies. Of course, many alternatives, variations, and modifications are possible without departing from this embodiment.

Closed loop adaptive clock RFI mitigation

A method according to one embodiment identifying the frequency range of at least one active channel of at least one wireless communication RF band; identifying the frequency range of at least one clock harmonic; identifying an overlap, in whole or in part, between the frequency range of the at least one active channel and the frequency range of the at least one clock harmonic; and shifting a fundamental frequency of the at least one clock to shift the frequency range of the at least one clock harmonic out of, at least in part, the frequency range of the at least one active channel. Of course, many alternatives, variations, and modifications are possible without departing from this embodiment.

Managing System Clocks to Reduce RFI

Techniques for reducing interference on radio frequencies due to processor frequencies which control a processor in wireless device are disclosed. A method for reducing interference on radio frequencies includes the steps of determining at least one radio frequency used in the wireless device and assigning an interference factor to a potential processor frequency corresponding to at least one radio frequency used in the wireless device. The method further includes the step of selecting a first processor frequency other than the potential processor frequency to avoid interference with the at least one radio frequency.

Methods and apparatus for radio frequency interference reduction

Provided are an image display apparatus and a laser projection apparatus, wherein a speckle noise can be reduced by a high frequency superimposition in order to provide a technology which makes it possible to prevent EMI while reducing a decrease in the amount of light to be emitted from a semiconductor laser. To this end, the display apparatus comprises a plurality of semiconductor lasers which emit laser beams having different wavelengths in accordance with drive currents supplied to the respective semiconductor lasers, a laser drive circuit which generates the respective drive currents by superimposing a plurality of high frequency signals on a plurality of respective image signals of color components, and a deflection means for deflecting each laser beam, wherein basic frequencies of the plurality of high frequency signals are different from each other.

Image display apparatus and laser projection apparatus

The present invention prevents performance degradation caused by a multiplication frequency of a memory clock in a wireless communication system by changing a frequency of the memory clock so that a multiplication frequency is not sufficiently close to a transmission/reception frequency that will cause noise or interference with a data transmission/reception. A communication apparatus according to the present invention includes a controller comprising at least one processor; and a memory for operating at a clock provided from the controller. The controller checks a communication frequency, determines whether the communication frequency is a value in a range of interference from a multiplication frequency of a memory clock frequency, and changes the memory clock frequency.

Apparatus and method for controlling memory clock frequency in wireless communication system

A method for selecting fundamental clock frequencies in order to achieve electromagnetic compatibility in electronic products which employ a plurality of clocks. The method require first selecting an ideal frequency for each clock in the product. Then, and until the goal of avoiding coinciding harmonics is complete, the method includes the steps of computing all harmonics of all clock frequencies chosen, determining a minimum difference tolerable in the chosen frequencies and their harmonics for sufficient minimization of electromagnetic interference, and determining if the harmonics of the chosen frequencies coincide impermissibly within the frequency range. If there exists coincidence of harmonics within the predetermined minimum range, then the fundamental frequency of at least one of the clocks corresponding to an interfering harmonic must be adjusted to eliminate the interference. With the altered fundamental frequency, the steps of computing harmonics, determining if coincidence occurs, and adjusting the fundamental frequency is repeated.

Michael B. Duich

Papers

Clock frequency coordination for electromagnetic compatibility