### Instruction:

Extract the cause and effect entities from the following sentence:
Several L-band technologies were identified as candidates to support future en route communication due to favorable propagation characteristics and because of spectrum congestion in the VHF band

### Assistant:

VARIABLE: spectrum congestion in the VHF band
CONDITION: favorable
KEYWORD: because of
AND: and
EFFECT_1: Several L-band technologies were identified as candidates to support future en route communication
CAUSE_1: favorable propagation characteristics
CAUSE_2: spectrum congestion in the VHF band

