ACK R-Data After

Last updated: January 16, 2009

This section is only applicable to the lab application and to a test application with the required feature license.

ACK R-Data After setting is used to emulate early termination on the reverse data channel (R-Data). It determines when the test set starts to send ACK bit on the forward ARQ channel upon reception of the R-Data subpackets.

ACK R-Data After setting is applicable when the test set is in the Active Cell operating mode with current physical layer subtype set to Subtype 2 (see Release A Physical Layer Subtype ) and the Active ARQ disabled (see Fixed Settings ).

In Subtype 2 physical layer operation, the AT can transmit up to four subpackets for each transmitted physical layer packet (see Background Information (Subpacket) ). The test set transmits a positive acknowledgment (ACK) or a negative acknowledgment (NAK) on the ARQ Channel in response to each received subpacket.

• The H-ARQ bit (Hybrid ARQ bit) is sent after the first (subpacket 0), second (subpacket 1) or third subpacket (subpacket 2) for a physical layer packet is received by the test set.
• The L-ARQ bit (Last ARQ bit) is sent after the reception of the fourth subpacket (subpacket 3).
• The P-ARQ bit (Packet ARQ bit) is sent after a physical layer packet has been successfully received (H-ARQ or L-ARQ sends ACK) or has failed to be received (L-ARQ sends NAK) after all four subpackets have been sent.

The following table shows the ACK/NAK bit patterns that are transmitted by the test set on the forward ARQ channel according to the ACK R-Data After setting and the actual received reverse data subpackets.

When Subpacket 0 (All ACK) is selected, an ACK bit will be sent on the ARQ channels for every subpacket received. When Never (All NAK) is selected, an NAK bit will be sent on the ARQ channels for every subpacket received.

ACK R-Data After setting defaults to Never (All NAK) which is to force the AT listening to the ARQ channel to send all four subpackets for each physical layer packet.

Different modulation schemes are used on the ARQ channel. The L-ARQ bit and the P-ARQ bit are modulated using NAK-oriented ON-OFF Keying (0 implies ACK, -1 implies NAK) while the H-ARQ modulation depends upon the setting of H-ARQ Modulation .