Abstract:
A high speed transmission system transfers data streams over a plurality of data links. Each data link may carry a number of bit streams. A clock signal is not transmitted over the optical link. Instead, an indication of the appropriate clock signal frequency and phase is embedded in the transmitted data. At the receiving end, a clock signal of an appropriate frequency and phase is generated. The new clock signal is used to sample and reconstruct the original data streams.
Abstract:
A high speed transmission system transfers data streams over a set of data links. Each data link may carry a number of bit streams. A clock signal is not transmitted over the optical link. Instead, an indication of the appropriate clock signal frequency and please is embedded in the transmitted data. At the receiving end, a clock signal of an appropriate frequency and phase is generated. The new clock signal is used to sample and reconstruct the original data streams.
Abstract:
A high speed transmission system transfers data streams over a plurality of data links. Each data link may carry a number of bit streams. On the transmitting end, multiplexers serialize the bit streams, which are then transmitted to the receiving end. A clock signal is not transmitted over the optical link. Instead, an indication of the appropriate clock signal frequency and phase is embedded in the transmitted data. At the receiving end, a clock recovery circuit generates a clock signal of an appropriate frequency and phase based on the embedded indication. The new clock signal is used to sample and reconstruct the original data streams.
Abstract:
The present invention provides an apparatus for generating a differential noise between a power and ground planes in a printed wiring board (PWB). The apparatus comprises a power plane, a ground plane, and a signal transmission circuit. A plurality of cuts comprising a first pattern is formed on the power plane. The ground plane also provides a plurality of cuts comprising a second pattern. Both the power plane and the ground plane are disposed in the PWB. A signal transmission circuit transmits a signal current over the ground plane and the power plane. The signal current induces an image return current on both the power plane and the ground plane. The first and second patterns of cuts on the power plane and the ground plane, respectively, disrupt the image return current and cause a differential voltage noise to be generated between the power plane and the ground plane.
Abstract:
A network device includes a group of high speed redundant transmission lines and a switch. The switch is configured to select one of the high speed redundant transmission lines. The switch causes reflections and frequency dependent dispersions in the selected high speed redundant transmission line. The network device further includes a transmitting device that is configured to adjust signals transmitted over the selected high speed redundant transmission line so as to reduce the reflections and frequency dependent dispersions.
Abstract:
A network device includes a group of high speed redundant transmission lines and a switch. The switch is configured to select one of the high speed redundant transmission lines. The switch causes reflections and frequency dependent dispersions in the selected high speed redundant transmission line. The network device further includes a transmitting device that is configured to adjust signals transmitted over the selected high speed redundant transmission line so as to reduce the reflections and frequency dependent dispersions.
Abstract:
A network device includes a group of high speed redundant transmission lines and a switch. The switch is configured to select one of the high speed redundant transmission lines. The switch causes reflections and frequency dependent dispersions in the selected high speed redundant transmission line. The network device further includes a transmitting device that is configured to adjust signals transmitted over the selected high speed redundant transmission line so as to reduce the reflections and frequency dependent dispersions.
Abstract:
A multi-loop phase lock loop (PLL) contains multiple loop filters, each having different bandwidths. The multi-loop PLL receives one of multiple high-frequency clock signals as an input. A phase detector outputs a signal, based on the phase difference between the high-frequency clock signal and a feedback signal to the loop filters. A voltage controlled oscillator generates an output clock signal based on signals received from the loop filters. During a clock switch over sequence between the multiple high-frequency input clock signals, the multi-loop PLL uses one of its loop filters with a wide bandwidth to quickly lock the input clock signal. Once the clock signal is locked, a narrower bandwidth loop filter in the PLL is then used to reduce jitter in the locked signal.