AMR Conformance testing

• GSM Tutorial
• GSM Frame Structure
• GSM Burst types
• GSM speech processing
• GSM Channel types-logical,physical
• GSM logical channels and mapping
• GSM Mobile network entry procedure
• GSM Mobile originated call flow
• GSM Mobile terminated call flow
• GSM Downlink PS Call
• GSM Uplink PS call
• GSM VAMOS Basics
• GSM AMR basics
• GSM noncombined channel configuration
• GSM combined channel configuration
• GSM Modulation types-MSK,GMSK
• GSM Physical Layer
• GSM Protocol Stack
• GSM Mobile Phone Basics
• GSM Radio Frequency Planning
• GSM MS Power Class
• GSM BTS Transceiver Power Class
• GSM Terminology
• GSM versus GPRS

Following are the AMR conformance test specifications to test AMR features in GSM compliant devices.

Loopback I: AMR Speech Channels

• SS is expected to transmit a valid DL signal including speech frames channel encoded as per CMI/DL.
• MS continuously transmits in UL the in-band bits decoded in DL. Decoded CMI/DL shall be looped as CMR/UL. Decoded CMC/DL shall be looped as CMI/UL.
• Default (ODD) transmission phase for CMI/CMC is assumed once in a loop.
• MS always uses codec mode which is resulted from received CMC for channel encoding.
• It uses fixed pattern of alternating 0 and 1 with 1st bit=1 (0x55 used in Hassium) and with TX_TYPE = SPEECH_GOOD.
• RATSCCH protocol is deactivated during loop I. No need to interpret content of DL RATSCCH message. No need to send RATSCCH_ACK.
• Loop I is only required to operate when DL DTX is NOT used.
is detected, no need for in band signalling loop back.
• Loop I is not designed to measure performance of in-band signalling over SID_UPDATE or RATSCCH messages.
• If FACCH is detected, MS sends all 0 pattern using same codec mode as previous UL frame. CMI/UL = uplink codec mode in use. CMR/UL = previous UL CMR.

AMR (TCH/AFS & TCH/AHS) Testing Conformance Tests

• Bad frames Indication (14.1.5, 14.1.6)
• Reference Sensitivity (14.2.10, 14.2.18)
• Co-channel Rejection (14.4.8, 14.4.16)
• Inband decoding performances (14.2.19, 14.2.20, 14.4.17, 14.4.18)
• Adjacent Channel Rejection (14.5.1)
• CMR computation performances (14.10.1, 14.10.2, 14.10.3, 14.10.4)
• DARP Phase-I (14.11.2, 14.11.3)
• DARP Phase-II (14.19.2, 14.19.3)
• Received signal measurements (with and without DTX) (21.3.3, 21.3.4, 21.3.5, 21.3.6, 21.4.2, 21.4.3)
• 26.16.x -> AMR signalling: AMR assignment, inband, ratscch, AMR HO

Companies such as Alcatel,Ericsson,Motorola,nortel,nokia and siemens has got facility to test AMR features in their respective IOT labs.

RF and Wireless Terminologies