Last updated: January 16, 2009
This section is only applicable to the lab application.
When a packet data connection is established (see How Do I Make a Packet Data Connection? ), the test set keeps a running count of the Radio Link Protocol (RLP) control messages, RLP user packets, and Internet Protocol (IP) packets as data is transferred. This information is recorded in the Data Counters table as shown in the figure below.
DOS Data counters: keep a running counter of DOS (Data Over Signaling) packets and bytes transferred on the reverse access channel.
When these DOS data counters reach their maximum value (10,000,000,000), they remain at that value until cleared.
RLP Control counters: keep a running count of RLP control messages transferred on both the forward and reverse traffic channels.
When these RLP control counters reach their maximum value (10,000,000,000), they automatically reset to zero and resume the count.
RLP Data counters: keep a running count of RLP user data for both the new and retransmitted octets transferred on both the forward and reverse traffic channels. A RLP packet is composed of a RLP header and a RLP payload (a number of user data octets).
When these RLP data counters reach their maximum value (10,000,000,000), they automatically reset to zero and resume the count
IP Data counters: keep a running counter of IP packets and bytes transferred on both the forward and reverse traffic channels.
When these IP data counters reach their maximum value (9,999,999,999), they remain at that value until cleared.
All of the data counters (including DOS, RLP and IP) will be cleared when the test set performs a power-up or full preset. You can also clear the RLP counters and IP counters individually (see How Do I Access the Data Counters? ).
Traffic Channel Packet Information is used to show the traffic activity on both the forward and reverse link. The information allows you to determine how many physical layer packets are transmitted or received at the particular data rate or packet size. The test set transmits the forward data packets at a rate requested by the AT via the DRC channel and determines the reverse traffic data rate detected from the R-RRI channel (the R-RRI channel is used by the AT to indicate the data rate at which the reverse traffic channel is transmitted). For the forward link, counters are also available at the particule data rate for the user to determine whether the packet failed at the physical layer and whether a failure at the physical layer transmission caused a retransmission based on Missed Preamble Retransmission (MPR).
The Forward Traffic Packet Failure Counters count the number of forward traffic packets transmitted by the test set to the AT where the preamble was detected by the AT but were not successfully demodulated by the AT at the physical layer.
The Forward Traffic Packet Missed Preamble Counters count the number of forward traffic packets transmitted by the test set where the AT appears to not have successful demodulated the preamble.
The Forward Traffic Packet Preamble Falsing Counter is used to indicate "falsing" of a forward traffic packet. Falsing happens when the AT incorrectly decodes a preamble. The test set receives power in the Reverse Ack Channel (Ack or Nak) for a physical packet when there was no associated packet directed to the AT. The Forward Traffic Packet Preamble Falsing Counter can only be incremented for physical packets that are not directed toward the AT.
When a data connection is established, the test set begins to accumulate the physical layer packets transmitted on both the forward and reverse traffic channels. If the data connection is disconnected, the packet accumulation will be suspended until another connection is made and the accumulation continues. Packet accumulation can be cleared by a power-up, full preset, measurement reset or an explicit clear operation, see To Clear Traffic Channel Packet Counters for details.
The test set provides two ways to view the traffic channel packet information:
Two sets of counters are available on the Traffic Channel Packet Info screen:
Forward Packets per DRC counters record the physical layer packets being sent on the forward traffic channel at each specific transmission format (data rate or packet size).
Total Directed counter records the total number of forward traffic packets that were directed to the AT under test. Not Directed counter records the total number of forward traffic packets that were not directed to the AT under test (that is, directed to a non-existent AT via a different MAC Index. See AT Directed Packets for more description).
Reverse Packets per Data Rate or Packet Size counters record the physical layer packets being received on the reverse traffic channel at each specific data rate or packet size. Null packets indicate the packets that do not contain traffic data.
When a data connection is established, all these counters keep a running count of the traffic packets sent at each specific transmission format since the counters were cleared. The counters are updated approximately once every second. When the counters reach their maximum value (100,000,000), they automatically reset to zero and resume the counting.
Forward Traffic Packet Failure per DRC counters record the physical layer packets transmitted by the test set where the preamble was detected by the AT but were not successfully demodulated by the AT at the physical layer, the pakcets are sent on the forward traffic channel at each specific transmission format (data rate or packet size).
Total Directed counter records the total number of forward traffic packets that were directed to the AT under test.
When a data connection is established, all these counters keep a running count of the packets sent at each specific transmission format since the counters were cleared. The counters are updated approximately once every second. When the counters reach their maximum value (100,000,000), they automatically reset to zero and resume the counting.
Forward Traffic Packet Missed Preamble per DRC counters record the physical layer packets transmitted by the test set where the AT appears to not have successful demodulated the preamble, the pakcets are sent on the forward traffic channel at each specific transmission format (data rate or packet size).
Total Directed counter records the total number of forward traffic packets that were directed to the AT under test.
When a data connection is established, all these counters keep a running count of the packets sent at each specific transmission format since the counters were cleared. The counters are updated approximately once every second. When the counters reach their maximum value (100,000,000), they automatically reset to zero and resume the counting.
As shown in the figure below, the Traffic Channel Packet Histogram screen uses both the bar graph and tabular data to show the forward traffic activity (per each DRC) when a data connection is established. The histogram screen only displays the forward traffic activity (the total number of forward traffic packets that is transmitted by the test set to the AT for the given DRC and transmission format) during the last (most recent)
Time Span
period.
Time Span
can be specified from 1 to 30 seconds. The Traffic Channel Histogram counters will be cleared whenever the
Time Span
is changed.
Freeze Histogram
and
Resume Histogram
. Note that the freezing action only pauses the display and does not stop the test set from counting. Once resumed, the Histogram display are updated to the last
Time Span
seconds of records based on the internal counters which continued to update while the histogram results were paused.
Time Span
in seconds and num_slots is the number of slots required to send a packet at that DRC and transmission format. (Note that even at 100% AT Directed Activity and no early termination the histogram bars can never reach the green line because control packets transmitted on the traffic channel are not counted).The following operations will clear all of the counters on the Traffic Channel Packet Info Screen and the Traffic Channel Packet Histogram :
Clear Traffic Counters
) key or send the
CALL:COUNt:CLEar:MS:TRAFfic
command.
Clear Histogram
) key or sending the
CALL:COUNt:CLEar:MS:TRAFfic:HISTogram
command;
Time Span
with
F1
key or the
CALL:COUNt:MS:DRC:RX:HISTogram:SPAN
.When a packet data connection is established for Multi-Flow Packet Application, the test set keeps a running count of the RLP user packets and Inernet Protocol (IP) packets per flow as data is transferred. This information is recorded in the figures Forward Link Sent Multi-Flow Counters Info and Reverse Link Received Multi-Flow Counters Info .
When these RLP control counters reach their maximum value (10,000,000,000), they automatically reset to zero and resume the count.
When these RLP data counters reach their maximum value (10,000,000,000), they automatically reset to zero and resume the count.
When these IP data counters reach their maximum value (9,999,999,999), they remainat that value until cleared.
All of the data counters (including RLP and Ip) will be cleared when the test set performs a power-up or full preset. You can also clear the RLP counters and Ip counters individually (see How Do I Access the Data Counters? ).
Manual Operation: How Do I Access the Data Counters?
GPIB commands: CALL:COUNt