Specifications

February 23, 2000 Motorola Personal Communications Sector Page 43
Satellite Subscriber Products Division
Motorola Personal Communications Sector
Satellite Subscriber Products Division
ISU AT Command Reference Extended Wireless Commands (+W)
8 Extended Wireless Commands (+W)
The following commands are specific to the IRIDIUM network and are taken from reference [5].
8.1 +WIRLP - IRIDIUM Radio Link Protocol
Set Command: +WIRLP=[<ver>[,<k1>[,<k2>[,< t1>[,<n2>[,<t2>[,<r1>[,<r2>[,<t4>[,<mode>]]]]]]]]]]
Set IRLP parameters.
<ver> specifies the desired IRLP version and can take the following values:
0 Default IRLP version (N0)
<k1> represents the maximum number of sequentially numbered I frames that may be outstanding
at any given time at downlink direction (IWF->ISU) and can take the following values: 1-105. Default is
105.
<k2> represents the maximum number of sequentially numbered I frames that may be outstanding
at any given time at uplink direction (ISU->IWF) and can take the following values: 1-105. Default is 105.
<t1> is used to supervise the acknowledgment of transmitted unnumbered frames. The values are
defined to be the earliest instant to enter the recovery procedure and can take on the following values: 27-255
(in 50-ms unit). Default is 30.
<n2> is used to represent the maximum number of re-transmission attempts of a frame (e.g.
I,S,N,U frame) and can take on the following values: 1-255. Default is 15.
<t2 > is used to indicate the amount of time available within the acknowledging frame must be
transmitted and can take on the following values: 1-255 (in 10-ms unit). Default is 10.
<r1> is used to represent the maximum number of S frames that are used to acknowledge I frames
at downlink direction (IWF->ISU) and can take on the following values: 1-10. Default is 10.
<r2 > is used to represent the maximum number of S frames that are used to acknowledge I frames
at uplink direction (ISU->IWF) and can take on the following values: 1-10. Default is 10.
<t4 > is used to supervise the re-sequencing of miss-ordered frames. The values are defined to be
the earliest instant to consider a tardy frame as lost. It can take on the following values: 20-255 (in 10-ms
unit). Default is 25.
<mode> is used to indicate the mode of operation and can take on the following values:
0 unacknowledged mode of operation
1 acknowledged mode of operation (default)
NOTE: For the proper operation of the IRLP procedures, T2 should be less than T1 and 2*T4 should be
less than T1.
Read Command: +WIRLP?
Query IRLP parameters. The response is in the form:
+WIRLP: <ver>, <k1>, <k2>, <t1>, <n2>, <t2>, <r1>, <r2>,
<t4>, <mode>
Test Command: +WIRLP=?
List the supported IRLP parameter settings. The response is in the form: