3.2.1 Demodulation of Forward Traffic Channel in AWGN

3.2.1 Demodulation of Forward Traffic Channel in AWGN

Last updated: January 15, 2009

Definition

Demodulation of Forward Traffic Channel in AWGN is the most important receiver test, for it tests the raw decoder ability of the baseband ASIC and the IF bandwidth of the access terminal (AT). This test evaluates how well the AT demodulates the Forward Traffic Channel in the presence of noise (how well it extracts the desired signal from the noise). The AWGN source simulates the interference power coming from surrounding cells when the AT is operating in a fully loaded network environment. The figure of merit is Packet Error Rate (PER).

Method of Measurement

  1. Connect the access network emulator and AWGN to the AT.
  2. Set the AN forward packet activity to 100%.
  3. Set the Control Channel data rate to 38.4 kbps (because the default power level for 38.4 kbps Control Channel is high enough to overcome the large AWGN power required for these tests).
  4. Set Pilot Drop to -14 dB (to prevent the access terminal from generating Pilot Strength Measurement Reports due to the low Pilot Channel to AWGN ratio).
  5. Set Î or to -55 dBm/1.23 MHz
  6. Set up a Test Application session and open an FTAP connection (for Subtype 0 or 1 Physical Layer).
  7. Perform tests 1 - 18 which evaluate the AT's performance at all Forward Traffic Channel data rates (38.4 to 2,457.6 kbps) that are supported by Subtype 0 or 1 Physical Layer for varying E b /N t . Set I oc as specified for each test.
  8. If your AT supports Subtype 2 Physical Layer, set Pilot Drop to -16 dB. Set up a Test Application session and open an FETAP connection (for Subtype 2 Physical Layer).
  9. Perform tests 19 - 30 which evaluate the AT's performance at Forward Traffic Channel data rates and transmission formats (such as short packets) that are only supported by Subtype 2 Physical Layer for varying E b /N t . Set I oc as specified for each test.
  10. If your AT supports Subtype 3 Physical Layer, Set up a Test Application session and open an FMCTAP connection (for Subtype 3 Physical Layer)
  11. For Subtype 3 Physical Layer, if the AT supports multi-carrier operation, perform tests 34 - 35 which evaluate the AT's performance at Forward Traffic Channel data rates and transmission formats that are only supported by Subtype 3 Physical Layer for varying E b /N t . Set I oc as specified for each test. Note that the data rate and geometry parameters are on a per carrier basis.
  12. Calculate PER for each test.

Minimum Standard

PER shall not exceed 0.5% to 5% with 95% confidence (depending upon data rate and E b /N t ).

   
NOTE
The following known Issue for 3.2.1 tests in C.S0033-B V1.0 will be fixed in next standard release:

  • The Î or /I oc for test 29 should be 23.44 dB resulting in a constant Î or value -55 dBm/1.23 MHz as for all other tests (1-28, and 30).
  • For Subtype 3 Physical Layer, if the AT supports rates higher than 3.072 Mbps, the Î or and I oc of test 31 - 33 are to be decided in next standard release.

       

Related Topics


Manual Operation: Testing 3.2.1 Demodulation of Forward Traffic Channel in AWGN

Programming a Packet Error Rate (PER) Measurement

Packet Error Rate (PER) Measurement Description

Packet Error Rate Measurement Troubleshooting