Abstract:
At least one channel is joined to a group of active channels in a communication system by transmitting control signals to configure respective customer premises equipment (CPE) of the active channels into a joining mode of operation, and transmitting a joining signature sequence to CPE of the joining channel over a downstream data signal path of the joining channel. A central office (CO) or other access node of the system receives correlation results from respective active channel CPE, estimates crosstalk from the joining channel into the active channels based on the correlation results, configures a precoder based on the estimated crosstalk, and adds the joining channel to the group of active channels. The channels may comprise respective subscriber lines of a DSL communication system.
Abstract:
Signature apparatus and techniques that make home networking devices, e.g., in-Home Phoneline Network (herein referred to as "HPN") devices, isolation filters, network interface devices, etc., detectable by commercially available metallic loop termination (MLT) test equipment. The invention also provides a method of testing a telephone line for the existence of a signature circuit identifying a home network. The home network signature circuit includes a series combination of a voltage breakdown device (e.g., Zener diodes) and an impedance (e.g., 200K ohm resistor). In operation, the home network signature circuit shunts the tested subscriber line loop with a voltage-dependent impedance in the presence of an appropriate test voltage exceeding 80 volts. Different high voltage thresholds of the voltage breakdown portion and/or different resistance values of the shunt impedance can be implemented in the home network signature device to produce uniquely detectable signatures. In this way, it is possible to remotely differentiate between various types of home network devices if the various types of home network devices include known voltage thresholds and/or shunt impedances. Loop qualification for services such as VDSL could include an automated remote scan from a central office for home network signature devices being served by telephone lines, e.g., existing in the same binder. To sense each of the parallel connected home network signature devices, the test equipment may preferably be made sensitive to the threshold voltage, not to the shunt impedance. The home network signature circuit may simply reside between the tip and ring on an HPN adapter. The home network signature circuit is preferably functional whether or not the network device is powered up. The home network signature circuit, in response to the activation energy signal exceeding a predetermined threshold above 80 volts, will drive an appropriate current back onto the telephone line.
Abstract:
A plurality of passive distributed POTS filters (12) are associated with a respective plurality of POTS communications devices and decouple a POTS CHANNEL from a telephone connection, while permitting and not interfering with a second communications channel (41) (e.g., DSL, ADSL, SDSL, RADSL, VADSL, etc.) on the telephone connection that is utilized by a modem. In architecture, the DPF system (10) includes a plurality of POTS communications devices, such as telephones, and a plurality of the DPFs (10) corresponding respectively with and connecting each of the POTS communications devices (33) to the telephone connection. Each of the DPFs comprise an automatic control mechanism and a POTS filter (12). The automatic control mechanism is configured to isolate the POTS filter when a respective POTS communications device is on-hook. Each DPF (10) is configured to permit POTS communications over a POTS channel on the telephone connection with the respective POTS communications device (33) when the POTS communications device is off-hook. Furthermore, a second communications device, such as a DSL (e.g., ADSL, SDSL, RADSL, VADSL, etc.) communications device, is connected to the telephone connection and communicates signals over a second channel. The POTS and second channel are communicated over the telephone connection concurrently without appreciable interference.