參數(shù)資料
型號: MH89760B
廠商: Mitel Networks Corporation
元件分類: 通信及網(wǎng)絡(luò)
英文描述: Ultraframer DS3/E3/DS2/E2/DS1/E1/DS0
中文描述: Ultraframer DS3/E3/DS2/E2/DS1/E1/DS0
文件頁數(shù): 16/38頁
文件大小: 846K
代理商: MH89760B
4-70
MH89760B
Preliminary Information
Figure 8 - Off-Line Framer State Diagram
Hunt Mode
False Candidate
False
Candidate
Forced
Reframe
Out of
Sync.
False
Candidate
Candidate
Candidate
CRC
Check
In sync
Candidate
*
Candidate
Valid Candidate
Resync
Receiver
Valid Candidate
New Frame Position
* Note: Only when in ESF mode and CRC
option is enabled.
Maintenance
Verify
detected a valid frame position. When the framer
exits maintenance mode the receive counters remain
where they are until the framer has found a new
frame position. This means that if the user forces a
reframe when the device was really in the right
place, there will not be any disturbance in the circuit
because the framer has no effect on the receiver
until it has found synchronization.
The out of
synchronization criterion can be controlled by bit 0 in
Master Control Word 2. This bit changes the out of
frame conditions for the maintenance state.
The out of sync threshold can be changed from 2 out
of 4 errors in F
T
(or FPS) to 4 out of 12 errors in F
T
(or FPS). The average reframe time is 24 ms for ESF
mode, and 12ms for D3/D4 modes.
Figure 9 is a bar graph which shows the probability
of achieving frame synchronization at a specific time.
The chart shows the results for ESF mode with CRC
check, and D3/D4 modes of operation. The average
reframe time with random data is 24 ms for ESF, and
13 ms for D3/D4 modes. The probability of a
reframe time of 35 ms or less is 88% for ESF
mode, and 97% for D3/D4 modes. In ESF mode it is
recommended that the CRC check be enabled
unless the line has a high error rate. With the CRC
check disabled the average reframe time is greater
because the framer must also check for mimics.
相關(guān)PDF資料
PDF描述
MH89760BN Ultraframer DS3/E3/DS2/E2/DS1/E1/DS0
MH89760BS Ultraframer DS3/E3/DS2/E2/DS1/E1/DS0
MH89761 T1 Transmit Equalizer Advance Information
MH89770N Ultraframer DS3/E3/DS2/E2/DS1/E1/DS0
MH89770 Ultraframer DS3/E3/DS2/E2/DS1/E1/DS0
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
MH89760BN 制造商:MITEL 制造商全稱:Mitel Networks Corporation 功能描述:ST-BUS⑩ FAMILY T1/ESF Framer & Interface Preliminary Information
MH89760BS 制造商:MITEL 制造商全稱:Mitel Networks Corporation 功能描述:ST-BUS⑩ FAMILY T1/ESF Framer & Interface Preliminary Information
MH89761 制造商:MITEL 制造商全稱:Mitel Networks Corporation 功能描述:T1 Transmit Equalizer Advance Information
MH89770 制造商:MITEL 制造商全稱:Mitel Networks Corporation 功能描述:T1/ESF Framer & Interface Preliminary Information
MH89770N 制造商:MITEL 制造商全稱:Mitel Networks Corporation 功能描述:T1/ESF Framer & Interface Preliminary Information