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SimGEN: How can I turn off individual frequencies on or off whilst a scenario is running, for example keep L1 on but turn L2 off?

  • SimGEN
  • multi-frequency simulator
  • One  way to do this is to use antenna switching on the receive antenna pattern.
    • define pattern 1 with both on
    • define pattern 2 with L1 on but L2 off
    • define switching file to switch between patterns as needed
  • The attached scenario "turn frequency off" demonstrates this principle as so:
    • at t=0 minutes L1 and L2 are both ON
    • at t=1 minutes L2 is turned OFF
    • at t=2 minutes L1 is turned OFF and L2 is turned on
  • Remember values in the antenna pattern represent attenuation in dB's so any negative values are gains!
  • The alternative way to achieve a similar effect is to use the Tx antenna patterns, this method allows you to configure different antenna patterns, one which can be considered normal levels and an alternative pattern which has the maximum attenuation applied. Switching the second antenna pattern in at a scheduled time gives the effect of turning of either L1 or L2 signals whilst continuing to transmit the wanted signal. The signal will still be produced by the configured channels but will be at a reduced level.
  • The attached scenario named "turn GPS L1 frequency off"  uses this method to  turn off the L1 off after an initial period of having both L1 and L2 signals.
  • Use of the " Antenna pattern selection file", which is a .aloc  file is used to achieve the switching
  • The level pattern #1 L1 and Level pattern#L2 files have the same characteristics as those used in the receive level pattern files, method 1 above.


Attachment Description
example scenario

Attachment Description
Initially L1 and L2 and then L2 only after 10 secs.

Product : SimGEN