Ericsson LBI-39224 manual Frame Format

LBI-39224

–Digital voice/data using subrate ports mode (currently not supported)

–Digital voice/data using T1/E1 mode (currently not supported)

Line Type

This is a read-only field which indicates which type of line (T1 or E1) that the system is configured for.

Frame Format

Framing deals with how the digitized data stream is configured (formatted), a data stream with one framing format would not be recognized by a system with another frame format. The possible T1 formats are 4-Frame Multiframe (F4), 12-Frame Multiframe (F12, D3/4), Extended Superframe (ESF), and Remote Switch Mode (F72). The possible E1 formats are Doubleframe and CRC Multiframe. The format is determined by the service line used. Select from the available choices in the drop-down list box to match the line format.

Line Code

The line code indicates the method used to encode long strings of zeroes. The receiving end of a T1/E1 link would not be able to remain in sync if long strings of zeroes were transmitted. The possible T1 line codes are B8ZS and AMI w/ZCS. The E1 line code is HDB3. The line code also is determined by the service line utilized. Select from the available choices in the drop-down list box to match the line.

Signaling Type

This signaling is used by the T1/E1 Interface Card to transmit channel status information (busy or idle). T1 uses bits robbed from the channel data to convey this information. E1 uses a dedicated channel to send signaling information for all channels; therefore only 30 user channels are allowed. In a CEC/IMC system, signaling must be set for MIM site interfaces, and the T1/E1 muxes and base stations at the associated site location must be configured for E&M Signaling unless the site is all digital (no analog voice). Signaling should not be set for any other device types. The types of signaling are No Signaling (both T1 and E1), Robbed Bit for T1, and CAS-CC for E1. Select the signaling type from the drop-down list box.

Line Length

This is the distance between the CEC/IMC and the device at the other end of the T1 line, which could be a microwave transceiver, a mux in co-located site equipment, CSU, etc. Line effects change the signal

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