Wavecom W 4010 User Manual page 22

The length of the transmitted blocks, the switching of the block lengths, and the data length are detected
automatically. The status line show the block lengths as short, middle, or long. The detection of block length
switching can be lost in case of heavy interference on the communications channel, in which case the key
[F2] should be pushed. The operating menu can be displayed with the MODE RECALL key which also ini-
tiates a new synchronization.
The SWED-ARQ utilizes 3 different block lengths. The short block corresponds principally to the mode SI-
TOR-ARQ. The system increases the block lengths automatically to middle or long when the communications
channel is good, while automatically reducing the block length as interference appears on the channel. To in-
crease the information transmission rate of a good quality channel, the middle block length makes it possible
to transmit and receive information at a rate of 75 Bauds, and with long block at a rate of 100 Bauds.
[F1] SPEED CHECK
[F2] PHASING
[F3] MODE RECALL
[F4] FORWARD SEQUENCE
[F4]+[F3] REVERSE SEQUENCE
ARQ6-90 is a simplex ARQ system similar to SITOR-ARQ with traffic blocking and acknowledgement on the
same frequency. The system uses 200 Baud as well as the SITOR alphabet with each block transmitting 6
characters.
Pressing the [F2] key causes signal to be rephased, while pressing the [F3] key recalls the operating mode
ARQ6-90. The polarity of the received signal is automatically recognized.
[F1] SPEED CHECK
[F2] PHASING
[F3] MODE RECALL
[F4] FORWARD SEQUENCE
[F4]+[F3] REVERSE SEQUENCE
ARQ6-98 is a simplex ARQ system similar to SITOR-ARQ with traffic blocking and acknowledgement on the
same frequency. The system uses 200 Baud as well as the SITOR alphabet with each block transmitting 6
characters.
Pressing the [F2] key causes signal to be rephased, while pressing the [F3] key recalls the operating mode
ARQ6-98. The polarity of the received signal is automatically recognized.
[F1] SPEED CHECK
[F2] BAUDRATE SELECTOR
[F3] MODE RECALL
[F4] FORWARD SEQUENCE
[F4]+[F3] REVERSE SEQUENCE
This FEC-Broadcast mode has a standard speed of 68.5 Baud.
The Bauer error-correcting code is a synchronous code with 10 bits per character. The first five bits are iden-
tical with the ITA No. 2, and the second five bits are a repetition of the first. However, when there is even
parity, the second 5 bits are transmitted inverted. The Bauer code is capable of correcting single-bit errors,
characters with more than one error are displayed with an underline character "_".
ARQ-98
Measure Baud rate
Rephases
Retrieves the operating mode
go to next operating mode
go to previous operating mode
ARQ6-90
Measure Baud rate
Rephases
Retrieves the operating mode
go to next operating mode
go to previous operating mode
AUTOSPEC
Displays the baud rate
Selects Baud rates manually
Redisplay of the mode as well as resynchronization
go to next operating mode
go to previous operating mode
- Page 22 -