摘要:
A headend communications device communicates via a network to downstream network elements, such as cable modems coupled behind optical network units, and allocates and grants timeslots for upstream transmissions from the network elements. The headend communications device has a scheduler for managing and controlling timeslot allocations in a manner avoiding interference such as optical beat interference or FM carrier collisions. The scheduler identifies two or more cable modems or like customer network elements served by the headend communications device that will cause at least a pre-determined intolerable level of interference when allocated overlapping timeslots for upstream transmissions and prevents these two or more cable modems or network elements from being allocated and granted overlapping timeslots.
摘要:
Described herein are devices and methods for facilitating the transmission of an upstream data signal from at least one subscriber in a communications network. The device is operable to receive a radio frequency (RF) signal from one or more subscribers. The RF signal includes at least one upstream data signal. The RF signal is demodulated into the upstream data signal by a RF demodulator in the device, which is then converted into an optical signal by an optical transducer in the device for transmission over a fiber optic link in the network.
摘要:
A headend communications device communicates via a network to downstream network elements, such as cable modems coupled behind optical network units, and allocates and grants timeslots for upstream transmissions from the network elements. The headend communications device has a scheduler for managing and controlling timeslot allocations in a manner avoiding interference such as optical beat interference or FM carrier collisions. The scheduler identifies two or more cable modems or like customer network elements served by the headend communications device that will cause at least a pre-determined intolerable level of interference when allocated overlapping timeslots for upstream transmissions and prevents these two or more cable modems or network elements from being allocated and granted overlapping timeslots.
摘要:
Described herein are devices and methods for facilitating the transmission of an upstream data signal from at least one subscriber in a communications network. The device is operable to receive a radio frequency (RF) signal from one or more subscribers. The RF signal includes at least one upstream data signal. The RF signal is demodulated into the upstream data signal by a RF demodulator in the device, which is then converted into an optical signal by an optical transducer in the device for transmission over a fiber optic link in the network.
摘要:
A system for providing power to a network interface device (NID) includes a primary power supply device (PPSD), a battery backup device (BBD), and an electrical bus connecting the PPSD, the BBD, and the NID in parallel. The PPSD is operable to power the NID. The BBD is configured to provide power to the NID in response to a power loss event, such as the PPSD failing to provide adequate power to the NID.
摘要:
A system for providing power to a network interface device (NID) includes a primary power supply device (PPSD), a battery backup device (BBD), and an electrical bus connecting the PPSD, the BBD, and the NID in parallel. The PPSD is operable to power the NID. The BBD is configured to provide power to the NID in response to a power loss event, such as the PPSD failing to provide adequate power to the NID.
摘要:
A gain variance and ingress reduction system reduces the overall ingress of interferers for an entire CATV system return transmission path and allows a reduction in subscriber terminal return transmitter power. The system places a calculated loss at each subscriber tap location. By placing these losses at each subscriber location, the headend receives a more consistent return transmission path gain thereby reducing the terminal return transmitter power range requirement. In addition, the losses reduce return transmission path ingress.