A clock signal generating apparatus detects a phase difference between an input reference clock signal and a feedback signal to output a control signal based on the phase difference, generates the clock signal with a frequency based on the output control signal, generates a pattern by switching, at a certain time interval, between a plurality of patterns of a second phase shift amount, adds a first phase shift amount to the second phase shift amount having the generated pattern, determines a phase to be selected, so that a cycle of the phase-shifted clock signal matches the cycle of a clock signal changed by the first phase shift amount to which the second phase shift amount is added, selects the determined phase from among a plurality of phases, and generates a phase-shifted clock signal whose signal level changes in the selected phase for output as the feedback signal.

An oscillation circuit includes: a periodic signal generator which generates a periodic signal whose frequency varies; and a clock generator which generates a clock signal having a frequency commensurate with the frequency of the periodic signal.

To provide a clock control circuit, a demodulation device, and a spread spectrum method, which can reduce interference caused by a clock signal on which spread spectrum is performed when demodulating a signal. A clock controller 22 according to the present invention disperses a harmonic of a clock signal in a used frequency band of a reception signal and controls a harmonic remaining in the used frequency band after the dispersion. For example, the clock controller 22 controls an amplitude of the harmonic on the basis of a spread frequency used for the dispersion and a spread width of the harmonic.

To provide a clock control circuit, a demodulation device, and a spread spectrum method, which can reduce interference caused by a clock signal on which spread spectrum is performed when demodulating a signal. A clock controller 22 according to the present invention disperses a harmonic of a clock signal in a used frequency band of a reception signal and controls a harmonic remaining in the used frequency band after the dispersion. For example, the clock controller 22 controls an amplitude of the harmonic on the basis of a spread frequency used for the dispersion and a spread width of the harmonic.

Decreasing interference of a first device operating according to high speed serial bus standard on a second device operating according to another different communication standard is provided. The method can include obtaining a first signal strength received by the second device before connection of the first device. The method can include obtaining a second signal strength received by the second device after connection of the first device and comparing the first signal strength and the second signal strength. If decrease of the second signal strength in comparison with the first signal strength exceeds a predetermined threshold, a command can be sent to the first device to enable the first device to operate at a lower bandwidth than the high speed serial bus standard.

Decreasing interference of a first device operating according to high speed serial bus standard on a second device operating according to another different communication standard is provided. The method can include obtaining a first signal strength received by the second device before connection of the first device. The method can include obtaining a second signal strength received by the second device after connection of the first device and comparing the first signal strength and the second signal strength. If decrease of the second signal strength in comparison with the first signal strength exceeds a predetermined threshold, a command can be sent to the first device to enable the first device to operate at a lower bandwidth than the high speed serial bus standard.

For wireless cellular communications, a “smart” multi-band combiner system has a multi-band combiner and a passive inter-modulation (PIM) detection sub-system. The multi-band combiner combines multiple transmit signals in different downlink frequency bands into a single, multi-band transmit signal for transmission from a cell tower antenna. The PIM detection sub-system characterizes the frequency components in the multi-band transmit signal to predict PIM products and determine if any predicted PIM products might interfere with any receive signals in any uplink frequency bands. If so, the PIM detection sub-system generates a signal indicating the presence of such predicted interfering PIM products, and the system installer and/or the network administrator can take remedial action to prevent the PIM products from interfering with user communications.

For wireless cellular communications, a “smart” multi-band combiner system has a multi-band combiner and a passive inter-modulation (PIM) detection sub-system. The multi-band combiner combines multiple transmit signals in different downlink frequency bands into a single, multi-band transmit signal for transmission from a cell tower antenna. The PIM detection sub-system characterizes the frequency components in the multi-band transmit signal to predict PIM products and determine if any predicted PIM products might interfere with any receive signals in any uplink frequency bands. If so, the PIM detection sub-system generates a signal indicating the presence of such predicted interfering PIM products, and the system installer and/or the network administrator can take remedial action to prevent the PIM products from interfering with user communications.

A device comprises a clock source configured to provide a spread-spectrum modulated clock signal and a control signal associated with the spread-spectrum modulated clock signal. The device also comprises a circuitry configured to receive the spread-spectrum modulated clock signal, to receive the control signal, and to sample a data signal in accordance with the spread-spectrum modulated clock signal and the control signal.

A device comprises a clock source configured to provide a spread-spectrum modulated clock signal and a control signal associated with the spread-spectrum modulated clock signal. The device also comprises a circuitry configured to receive the spread-spectrum modulated clock signal, to receive the control signal, and to sample a data signal in accordance with the spread-spectrum modulated clock signal and the control signal.