Outer code covered synchronous code division multiple access for cable modem channels

A cable modem system that is operable using synchronous code division multiple access for a plurality of cable modem channels, the cable modem system comprising:

• a plurality of cable modems;
• a cable modem termination system;
• and
• a cable modem network segment that communicatively couples the cable modem termination system to the plurality of cable modems;
• and wherein:
• the cable modem termination system is operable to provide network access to each cable modem within the plurality of cable modems, the network access being provided using a plurality of cable modem user signals, each cable modem user signal being transmitted from the cable modem termination system to at least one of the cable modems within the plurality of cable modems;
• each of the plurality of cable modems spreads its respective cable modem user signal using its respective orthogonal code of a plurality of orthogonal codes to generate its respective orthogonal code spread cable modem user signal;
• each of the plurality of cable modes spreads its respective orthogonal code spread cable modem user signal using a pseudo-noise code, that is common to all of the plurality of cable modems, to generate a pseudo-noise code spread cable modem user signal;
• the cable modem termination system de-spreads each respective pseudo-noise code spread cable modem user signal using the pseudo-noise code to generate a respective pseudo-noise code de-spread signal;
• the cable modem termination system de-spreads each respective pseudo-noise code de-spread signal using the orthogonal code employed by the respective cable modem to generate the respective orthogonal code de-spread signal;
• and
• each orthogonal code of the plurality of orthogonal codes corresponds to one respective cable modem of the plurality of cable modems.

A cable modem, implemented within a cable modem system, that is operable using synchronous code division multiple access, the cable modem comprising:

• a transmit block comprising an orthogonal code spreader and a pseudo-noise spreader;
• and
• a receive block comprising a pseudo-noise de-spreader and an orthogonal code de-spreader;
• and wherein:
• the transmit block being operable to spread a cable modem user signal using the orthogonal code spreader to generate an orthogonal code spread cable modem user signal;
• the transmit block being operable to spread the orthogonal code spread cable modem user signal using the pseudo-noise code spreader to generate a pseudo-noise code spread cable modem user signal;
• the receive block being operable to de-spread a received cable modem user signal using the pseudo-noise code de-spreader to generate an orthogonal code de-spread cable modem user signal;
• the receive block being operable to de-spread the orthogonal code de-spread cable modem user signal using the orthogonal code de-spreader;
• the orthogonal code spreader and the orthogonal code de-spreader employ a same orthogonal code unique to the cable modem;
• each of the pseudo-noise spreader and the pseudo-noise de-spreader employs a same pseudo-noise code employed by all other cable modems within the cable modem system in accordance with spreading respective cable modem user signals and de-spreading respective received pseudo-noise code spread cable modem user signals;
• and
• the orthogonal code employed by the orthogonal code spreader and the orthogonal code de-spreader is different than all other orthogonal codes employed by all other cable modems within the cable modem system.

A cable modem system that is operable using synchronous code division multiple access for a plurality of cable modem channels, comprising:

• a plurality of cable modems such that each of the plurality of cable modems includes a respective pseudo-noise de-spreader and a respective orthogonal code de-spreader;
• and wherein:
• each of the plurality of cable modems receives a pseudo-noise code signal;
• each of the plurality of cable modems employs its respective pseudo-noise de-spreader, that operates using a pseudo-noise code that is common to all of the plurality of cable modems, to de-spread the pseudo-noise code signal thereby generating its respective pseudo-noise de-spread cable modem user signal;
• each of the plurality of cable modems de-spreads its respective pseudo-noise de-spread cable modem user signal using its respective orthogonal code;
• and
• each of the plurality of orthogonal codes corresponds to one respective cable modem of the plurality of cable modems.

A method, comprising:

• spreading a first input signal using a first orthogonal code, of a plurality of orthogonal codes, thereby generating a first orthogonal code spread signal;
• spreading a second input signal using a second orthogonal code, of the plurality of orthogonal codes, thereby generating a second orthogonal code spread signal;
• summing the first orthogonal code spread signal and the second orthogonal code spread signal thereby generating a summed spread signal;
• spreading the summed spread signal using a pseudo-noise code thereby generating a pseudo-noise code spread signal;
• from a transmitter, transmitting the pseudo-noise code spread signal to a receiver of a plurality of receivers such that each orthogonal code of the plurality of orthogonal codes corresponds to one respective receiver of the plurality of receivers;
• within the receiver, de-spreading the pseudo-noise code spread signal using the pseudo-noise code thereby generating a pseudo-noise code de-spread signal;
• and
• de-spreading the pseudo-noise code de-spread signal using the first orthogonal code thereby generating an orthogonal code de-spread signal.

A method, comprising:

• within a transmitter, receiving an enable signal;
• spreading a first input signal using a first orthogonal code, of a plurality of orthogonal codes, thereby generating a first orthogonal code spread signal;
• spreading a second input signal using a second orthogonal code, of the plurality of orthogonal codes, thereby generating a second orthogonal code spread signal;
• summing the first orthogonal code spread signal and the second orthogonal code spread signal thereby generating a summed spread signal;
• selectively spreading the summed spread signal, based on the enable signal, using a pseudo-noise code thereby generating a pseudo-noise code spread signal;
• and
• from the transmitter, based on the enable signal, transmitting either the pseudo-noise code spread signal or the summed spread signal to a plurality of receivers such that each orthogonal code of the plurality of orthogonal codes corresponds to one respective receiver of the plurality of receivers.