Method to mitigate the near-far fext problem

A method for reducing cross-talk in a communication system, the communication system including a central unit, two or more remote units, each of the remote units communicatively coupled to the central unit through a channel, wherein the channels are located relative to each other such that a transmission to or from a one of the remote units that passes through a one of the channels creates cross-talk interference in one or more of the other channels, the method comprising:

• measuring a first channel between the central unit and a first remote unit and providing a transfer function of the first channel;
• and
• adjusting a transmission of a second remote unit passing through a second channel communicatively coupling a second remote unit with the central unit, the transmission having a spectral shape, the adjustment shaping the spectral shape of the transmission of the second remote unit passing through the second channel such that cross-talk interference in the first channel is reduced.

A transceiver for use in a communication system, wherein the transceiver is one of two or more transceivers in the communication system, the communication system further comprising a central unit, each of the transceivers communicatively coupled to the central unit through a channel, each channel having a characteristic, wherein the transceiver transmits a signal to the central unit across a channel, the signal being spectrally shaped such that interference generated on the other channels by the signal, while transmitted across the channel, is reduced.

A transceiver for use in a communication system, wherein the transceiver is one of two or more transceivers in the communication system, the communication system further comprising a central unit, each of the remote units communicatively coupled to the central unit through a channel, each channel having a characteristic, wherein the transceiver transmits a signal to the central unit across a channel the signal being spectrally shaped such that interference generated by the signal while transmitted across the channel on the other channels is reduced;

• and,
• wherein the signal being transmitted by the central unit across the channel is a multi-carrier signal including a plurality of carriers, each carrier centered at a frequency over a span of frequencies.

A central unit for use in a communication system, the communication system including two or more remote units, each of the remote units communicatively coupled to the central unit by a channel, the remote units sending and receiving transmissions to and from the central unit, wherein the central unit measures a characteristic of a first channel of a first remote unit, and adjusts a transmission of a second remote unit carried on a second channel based upon the characteristic of the first channel, the adjusting of the transmission of the second remote unit reducing cross-talk interference generated by the transmission carried on the second channel and received by the first channel.

A central unit for use in a communication system, the communication system including two or more remote units, each of the remote units communicatively coupled to the central unit by a channel, the remote units sending and receiving transmissions to and from the central unit, wherein the central unit measures a characteristic of a first channel of a first remote unit, and adjusts a transmission of a second remote unit carried on a second channel based upon the characteristic of the first channel, the adjusting of the transmission of the second remote unit reducing cross-talk interference generated by the transmission carried on the second channel and received by the first channel;

• and,
• wherein the transmission of the second remote unit is a multi-carrier signal including a plurality of carriers, each carrier centered at a frequency over a span of frequencies.

A central unit for use in a communication system, the communication system including two or more remote units, each of the remote units communicatively coupled to the central unit by a channel, the remote units sending and receiving transmissions to and from the central unit, wherein the central unit measures a characteristic of a first channel of a first remote unit, and adjusts a transmission of a second remote unit carried on a second channel based upon the characteristic of the first channel, the adjusting of the transmission of the second remote unit reducing cross-talk interference generated by the transmission carried on the second channel and received by the first channel;

• wherein the central unit adjusts the transmission of the second remote unit by providing the second remote unit with a desired power spectral density such that the second remote unit transmits at a transmit power spectral density such that the central unit receives the desired power spectral density;
• and,
• wherein the adjusting of the multi-carrier transmission is performed on a subset of the plurality of carriers over a corresponding sub-range of frequencies of the range of frequencies.

A method of shaping transmissions between a plurality of remote units and a central unit, each of the remote units coupled to the central unit through a channel, each remote unit sending a transmission to the central unit, each transmission having a spectrum, the method comprising:

• adjusting the transmission of the remote units such that the transmissions of all of the remote units have approximately identical spectrums as received by the central unit;
• wherein the adjusting of the transmissions of the remote units reduces the cross-talk between the channels of the remote units.