ADC MM701G2, MM702G2 user manual Data Rate kbps, PSD Mode

April 14, 2006 Appendix A: Command Line Interface Access

Step Action

2• Data Rate (kbps)

(cont.)	Type 4 then select a data rate (number 1 through 34) which determines the maximum transmission
	rate, in kilobits per second, up to which the modem can negotiate and synchronize with another
	device (modem or a DSLAM) to which it is attached. When the Bit Rate Mode (see “Bit Rate Mode”
	below) is set to Fixed, the range of values are (ADC modems comply with the standard G.shdsl data
	rate range):

–for the MM702G2 modem, 384 kbps to 4608 kbps, in 128 kbps increments

–for the MM701G2 modem, 192 kbps to 2304 kbps, in 64 kbps increments

–Rates down to 64 kbps are supported only when operating in single-pair, point-to-point mode with another ADC modem. The default value is Adaptive. (see Chapter 7: Implementing a Point- To-Point LAN Extension).

•Wire Pair Mode

Type 5 then select a wire mode. For the MM701G2 modem, Single mode is the only setting available. For the MM702G2 modem, you can select 1 for Single, 2 for Dual mode, or 3 for Dual Enhanced mode. Single mode is the default. Wire mode indicates whether the G.shdsl modem is operating in a two-wire mode (Single), a four-wire mode (Dual), or a Dual Enhanced mode. Dual Enhanced mode is a two-pair rate-adaptive mode.

•PSD Mode

Type 6 then select which Power Spectral Density (PSD) which plots the variations of signal power with signal frequency for the G.shdsl transmission between the modem and the DSLAM or the modem and another modem. Select 1 for Symmetric PSD which indicates that the PSD mask for both sides of the transmission (the CO- and remote-side) are the same (symmetric).

Asymmetric PSD indicates that the PSD mask for both sides of the transmission (the CO- and remote-side) are not the same (asymmetric). There are two unique numeric values (AsymmetricRate1 and AsymmetricRate2) used to determine the asymmetric PSD mask based on the Annex A or Annex B standard that you selected. Select 2 for AsymmetricRate1 which is 784 kbps for Annex A and 2312 kbps for Annex B. Select 3 for AsymmetricRate2 which is 1552 kbps for Annex A and 2056 kbps for Annex B.

Both ends of the connection must be set for the same Symmetric or Asymmetric PSD. The default is Symmetric.

•Bit Rate Mode

Type 4 then select either 1 for Adaptive or 2 for Fixed mode. Bit rate mode indicates how the modem synchronizes with the device to which it is attached. The default for the modem is Adaptive mode. The following provides more description for each mode.

–Fixed mode indicates that the modem will synchronize with the other end (a DSLAM or another modem) at a fixed bit rate through negotiation. The modem will synchronize at the best rate, up to the data rate specified (see “Data Rate (kbps)” above), that can be achieved by both ends.

–Adaptive mode indicates that prior to modem negotiating a rate, the modem performs an adaptation phase during which it determines a best possible rate based on conditions of the line. After adaptive mode, the modem will then negotiate the best rate that can be achieved with the other end, based on the adaptation results. The default is Adaptive.

MM70xG2-UM-03 A-21