BIT Analyzer Synchronization Configuration

Availability

SkySweeper Lite : NO
SkySweeper STD : NO
SkySweeper STD+ : NO
SkySweeper PRO : YES

 

General description

This is a tool for bit synchronizing. It provides three main types of synchronization: manual, sync word and ¾ sync. Manual sync means that the bit synchronization is adjusted manually, bit position by bit position to forward or backward. Sync word means that the predefined sync word will be searched for in the bit stream (This is very useful in decoding transmissions like MPT-1327 and POCSAG). 3/4 sync means, that several sequential 7 bit figures containing (3 zeros and 4 ones) will be searched (this used in SITOR-A etc.).

Configuration

 

 

Parameters

 

Sync Method

This is the operational mode of the sync block. There are three main types of synchronization: manual, sync word and ¾ sync. Manual sync means that the bit synchronization is adjusted manually bit position by bit position to forward or backward. Sync word means, that the predefined sync word will be searched for in the bit stream. 3/4 sync means, that several sequential 7 bit figures containing (3 zeros and 4 ones) will be searched (this used in SITOR-A etc.).

Sync Word as Bits

This is active only if the Sync Word Based Sync is in use. This is the sync word, in bits, to be searched for.

Trigger sync

This is active only if Sync Word Based Sync is in use. When this is selected the given sync word is searched for once only. When the trigger word has been found, printing of the bits is started, without any breaks.

Packet sync

This is active only if Sync Word Based Sync is in use. When this is selected the given sync word is searched for and when it has been found the bits of this packet will be printed out. The packet is always limited in size (see packet sync). When this packet has been printed out, the next new packet will be searched for.

 

Trigger sync parameters

Automatic Re Sync

This is active only if Sync Word Based Sync and Trigger Sync is in use. When this is selected the given sync word is always searched for and when it is found, the bit stream will be synchronized again.

Re Sync Button

When the button is pressed synchronization is restarted.

Number of bits before the sync word

This is active only if Sync Word Based Sync and Packet Sync is in use. This is the number of bits that will be printed before the sync word of the packet.

 

Number of bits after the sync word

This is active only if Sync Word Based Sync and Packet Sync is in use. This is the number of bits that will be printed after the sync word of the packet.

¾ sync settings

This is active only if 3/4 sync is in use. This is the number of characters used in determining the bit sync and also the number characters.

Back

This is active only if manual sync is in use. It shifts the bit stream back by one bit position.

Forward

This is active only if manual sync is in use. It shifts the bit stream forward by one bit position.

Multiple Sync Windows

This actives N sync windows (N equals the number of the bits in char). If 7-bit ASCII is received, then 7 windows with different bit sync will be opened (there’s one window with correct bit sync in all the time). The sync windows can be opened by clicking the buttons "shift1…shiftN" over the text box in the bit analyzer.