Question: In 3GPP-compliant Base Station (BS) conformance testing for FDD, what is a key determinant of the Random Access Channel (RACH) performance requirement in high-speed train conditions?
Option 1: Maximum transmission power of the User Equipment (UE)
Option 2: Minimum number of retransmissions allowed for a successful access
Option 3: Type of antenna configuration used at the Base Station (BS)
Option 4: Maximum Block Error Ratio (BLER) at a specified Eb/N0 limit
Explanation: The correct answer is Option 4 because, according to the specifications for BS conformance testing in high-speed train conditions, the RACH performance requirement is directly tied to the maximum allowable Block Error Ratio (BLER) when the receiver's input signal reaches a specific Eb/N0 (Energy per bit to Noise power spectral density ratio) threshold. This ensures reliable access and communication under challenging, high-mobility scenarios.