Abstract: An example communication system in a cellular network comprises: a processing system comprising a controller and remote units, with the remote units being configured to communicate with the controller and to communicate with mobile devices within a communication cell of the cellular network. At least part of the processing system is configured to perform operations comprising: estimating signal strength experienced by all or some of the mobile devices; identifying, based at least on the signal strength, one or more of the mobile devices that can be scheduled for communication with one or more of the remote units in the communication cell on a same airlink resource; and scheduling the communication.

Abstract: Among other things, a communication system comprising remote units, a reference timing source, a controller, a controller clock, and a remote unit clock. The remote units exchange radio frequency (RF) signals with mobile devices. The reference timing source is synchronized with a coordinated universal time (UTC) or a Global Positioning System (GPS). The controller clock is synchronized with the reference timing source and provides timing information to the controller. The remote unit clock is synchronized with the controller clock and provides timing information to a remote unit. The controller and the remote unit are configured to transmit time stamp messages to synchronize the controller clock and the remote unit clock, by avoiding contention between time stamp transmissions and baseband data transmissions or between time stamp transmissions of different remote units to the controller.

Abstract: Described herein are implementations related to the generation of probe frames. In one implementation, a generated probe frame includes two symbols, where the two symbols are different. In one implementation, a first of the two symbols is a probe symbol and a second of the two symbols is a quiet symbol.

Abstract: An example communication system in a cellular network comprises: a processing system comprising a controller and remote units, with the remote units being configured to communicate with the controller and to communicate with mobile devices within a communication cell of the cellular network. At least part of the processing system is configured to perform operations comprising: estimating signal strength experienced by all or some of the mobile devices; identifying, based at least on the signal strength, one or more of the mobile devices that can be scheduled for communication with one or more of the remote units in the communication cell on a same airlink resource; and scheduling the communication.

Abstract: There are several exemplary ways to more efficiently communicate an out-of-domain seed to a receiver—in a first technique, the seed can be indicated in the header portion or data portion of a packet. For example, the header portion of the packet could contain one or more bit fields that indicate the value of the LFSR seed used for the preamble portion of the packet. The receiver would learn the out-of-domain seed after receiving a first out-of-domain packet and decoding the header portion of that packet. After learning the out-of-domain seed, the receiver could send a packet indicating the value of the out-of-domain seed to the local master. The local master could then transmit the value of the out-of-domain seed in the header portion or data portion of a local MAP frame.

Abstract: An echo cancellation device relies on the known characteristics of the sync frame to monitor, update in an off-line fashion and determine the accuracy of an echo canceller in, for example, a modem, such as an ADSL modem. Specifically, time domain samples are read from the transmit (Tx) and receive (Rx) paths of the modem. These samples are stored in memory. When the sync frame has received a predetermined number of the same Tx samples and Rx samples, the samples are stored. Running averages, over the sync frames, of the TX and RX samples are maintained. These averages are subtracted from a sync frame of samples, to allow LMS updating of the echo canceller taps, free of extraneous signals. Updating, i.e., tracking of changes in the echo channel, is done for the echo canceller in an off-line fashion. The coefficients for the in-line version are updated, while the off-line version is updated over several sync frames. Periodically, the performance of the off-line version is compared with the in-line version.

Abstract: There are several exemplary ways to more efficiently communicate an out-of-domain seed to a receiver—in a first technique, the seed can be indicated in the header portion or data portion of a packet. For example, the header portion of the packet could contain one or more bit fields that indicate the value of the LFSR seed used for the preamble portion of the packet. The receiver would learn the out-of-domain seed after receiving a first out-of-domain packet and decoding the header portion of that packet. After learning the out-of-domain seed, the receiver could send a packet indicating the value of the out-of-domain seed to the local master. The local master could then transmit the value of the out-of-domain seed in the header portion or data portion of a local MAP frame.

Abstract: There are several exemplary ways to more efficiently communicate an out-of-domain seed to a receiver—in a first technique, the seed can be indicated in the header portion or data portion of a packet. For example, the header portion of the packet could contain one or more bit fields that indicate the value of the LFSR seed used for the preamble portion of the packet. The receiver would learn the out-of-domain seed after receiving a first out-of-domain packet and decoding the header portion of that packet. After learning the out-of-domain seed, the receiver could send a packet indicating the value of the out-of- domain seed to the local master. The local master could then transmit the value of the out- of-domain seed in the header portion or data portion of a local MAP frame.

Abstract: An echo cancellation device relies on the known characteristics of the sync frame to monitor, update in an off-line fashion and determine the accuracy of an echo canceller in, for example, a modem, such as an ADSL modem. Specifically, time domain samples are read from the transmit (Tx) and receive (Rx) paths of the modem. These samples are stored in memory. When the sync frame has received a predetermined number of the same Tx samples and Rx samples, the samples are stored. Running averages, over the sync frames, of the TX and RX samples are maintained. These averages are subtracted from a sync frame of samples, to allow LMS updating of the echo canceller taps, free of extraneous signals. Updating, i.e., tracking of changes in the echo channel, is done for the echo canceller in an off-line fashion. The coefficients for the in-line version are updated, while the off-line version is updated over several sync frames. Periodically, the performance of the off-line version is compared with the in-line version.

Abstract: There are several exemplary ways to more efficiently communicate an out-of-domain seed to a receiver—in a first technique, the seed can be indicated in the header portion or data portion of a packet. For example, the header portion of the packet could contain one or more bit fields that indicate the value of the LFSR seed used for the preamble portion of the packet. The receiver would learn the out-of-domain seed after receiving a first out-of-domain packet and decoding the header portion of that packet. After learning the out-of-domain seed, the receiver could send a packet indicating the value of the out-of-domain seed to the local master. The local master could then transmit the value of the out-of-domain seed in the header portion or data portion of a local MAP frame.

Abstract: There are several exemplary ways to more efficiently communicate an out-of-domain seed to a receiver—in a first technique, the seed can be indicated in the header portion or data portion of a packet. For example, the header portion of the packet could contain one or more bit fields that indicate the value of the LFSR seed used for the preamble portion of the packet. The receiver would learn the out-of-domain seed after receiving a first out-of-domain packet and decoding the header portion of that packet. After learning the out-of-domain seed, the receiver could send a packet indicating the value of the out-of-domain seed to the local master. The local master could then transmit the value of the out-of-domain seed in the header portion or data portion of a local MAP frame.

Abstract: Among other things, a communication system comprising remote units, a reference timing source, a controller, a controller clock, and a remote unit clock. The remote units exchange radio frequency (RF) signals with mobile devices. The reference timing source is synchronized with a coordinated universal time (UTC) or a Global Positioning System (GPS). The controller clock is synchronized with the reference timing source and provides timing information to the controller. The remote unit clock is synchronized with the controller clock and provides timing information to a remote unit. The controller and the remote unit are configured to transmit time stamp messages to synchronize the controller clock and the remote unit clock, by avoiding contention between time stamp transmissions and baseband data transmissions or between time stamp transmissions of different remote units to the controller.

Abstract: Described herein are implementations related to the generation of probe frames. In one implementation, a generated probe frame includes two symbols, where the two symbols are different. In one implementation, a first of the two symbols is a probe symbol and a second of the two symbols is a quiet symbol.

Abstract: An echo cancellation device relies on the known characteristics of the sync frame to monitor, update in an off-line fashion and determine the accuracy of an echo canceller in, for example, a modem, such as an ADSL modem. Specifically, time domain samples are read from the transmit (Tx) and receive (Rx) paths of the modem. These samples are stored in memory. When the sync frame has received a predetermined number of the same Tx samples and Rx samples, the samples are stored. Running averages, over the sync frames, of the TX and RX samples are maintained. These averages are subtracted from a sync frame of samples, to allow LMS updating of the echo canceller taps, free of extraneous signals. Updating, i.e., tracking of changes in the echo channel, is done for the echo canceller in an off-line fashion. The coefficients for the in-line version are updated, while the off-line version is updated over several sync frames. Periodically, the performance of the off-line version is compared with the in-line version.

Abstract: There are several exemplary ways to more efficiently communicate an out-of-domain seed to a receiver—in a first technique, the seed can be indicated in the header portion or data portion of a packet. For example, the header portion of the packet could contain one or more bit fields that indicate the value of the LFSR seed used for the preamble portion of the packet. The receiver would learn the out-of-domain seed after receiving a first out-of-domain packet and decoding the header portion of that packet. After learning the out-of-domain seed, the receiver could send a packet indicating the value of the out-of-domain seed to the local master. The local master could then transmit the value of the out-of-domain seed in the header portion or data portion of a local MAP frame.

Abstract: An echo cancellation device relies on the known characteristics of the sync frame to monitor, update in an off-line fashion and determine the accuracy of an echo canceller in, for example, a modem, such as an ADSL modem. Specifically, time domain samples are read from the transmit (Tx) and receive (Rx) paths of the modem. These samples are stored in memory. When the sync frame has received a predetermined number of the same Tx samples and Rx samples, the samples are stored. Running averages, over the sync frames, of the TX and RX samples are maintained. These averages are subtracted from a sync frame of samples, to allow LMS updating of the echo canceller taps, free of extraneous signals. Updating, i.e., tracking of changes in the echo channel, is done for the echo canceller in an off-line fashion. The coefficients for the in-line version are updated, while the off-line version is updated over several sync frames. Periodically, the performance of the off-line version is compared with the in-line version.

Abstract: An echo cancellation device relies on the known characteristics of the sync frame to monitor, update in an off-line fashion and determine the accuracy of an echo canceller in, for example, a modem, such as an ADSL modem. Specifically, time domain samples are read from the transmit (Tx) and receive (Rx) paths of the modem. These samples are stored in memory. When the sync frame has received a predetermined number of the same Tx samples and Rx samples, the samples are stored. Running averages, over the sync frames, of the TX and RX samples are maintained. These averages are subtracted from a sync frame of samples, to allow LMS updating of the echo canceller taps, free of extraneous signals. Updating, i.e., tracking of changes in the echo channel, is done for the echo canceller in an off-line fashion. The coefficients for the in-line version are updated, while the off-line version is updated over several sync frames. Periodically, the performance of the off-line version is compared with the in-line version.

Abstract: There are several exemplary ways to more efficiently communicate an out-of-domain seed to a receiver—in a first technique, the seed can be indicated in the header portion or data portion of a packet. For example, the header portion of the packet could contain one or more bit fields that indicate the value of the LFSR seed used for the preamble portion of the packet. The receiver would learn the out-of-domain seed after receiving a first out-of-domain packet and decoding the header portion of that packet. After learning the out-of-domain seed, the receiver could send a packet indicating the value of the out-of-domain seed to the local master. The local master could then transmit the value of the out- of-domain seed in the header portion or data portion of a local MAP frame.

Abstract: Adjusted maximum transmit PSD levels have an effect on the SNR. If the ADC noise is assumed to be the limiting factor, then there can be a benefit for reducing the maximum transmit PSD level. For example, by lowering the maximum transmit PSD level from ?50 dBm/Hz to ?70 dBm/Hz results in an increase in SNR for subcarriers above 30 M Hz. The SNR for subcarriers above 30 MHz can increase from 30 db (?80-(?110)) to 50 db (?80-(?130)). Therefore, by changing the maximum transmit PSD level, applying a ceiling on PSD mask, the aggregate sum of the available SNR's over the available subcarriers is therefore increasing the obtainable OFDM data rate. In other words, a maximum transmit PSD mask can be used to lower the transmit PSD value of at least one subcarrier which results in an increase in SNR for at least one subcarrier.

Abstract: Adjusted maximum transmit PSD levels have an effect on the SNR. If the ADC noise is assumed to be the limiting factor, then there can be a benefit for reducing the maximum transmit PSD level. For example, by lowering the maximum transmit PSD level from ?50 dBm/Hz to ?70 dBm/Hz results in an increase in SNR for subcarriers above 30 MHz. The SNR for subcarriers above 30 MHz can increase from 30 db (?80?(?110)) to 50 db (?80?(?130)). Therefore, by changing the maximum transmit PSD level, applying a ceiling on PSD mask, the aggregate sum of the available SNR's over the available subcarriers is increased, therefore increasing the obtainable OFDM data rate. In other words, a maximum transmit PSD mask can be used to lower the transmit PSD value of at least one subcarrier which results in an increase in SNR for at least one subcarrier.