Lte Eran7.0 Intra-rat Handover Feature

Explanation
Using event A4 to trigger inter-freq handover is faster because it is based on measurement reports from the UE (User Equipment) indicating a significant deterioration in the signal quality of the current serving cell. This allows for a quicker decision to initiate the handover process. On the other hand, event A5 is more accurate as it is based on measurement reports indicating a better signal quality in the target cell compared to the serving cell. However, it requires more time to collect these measurements, making it slower compared to event A4. Therefore, the statement is true.

Explanation
To enter Gap Assisted Measurement, A2 does not need to be triggered. Therefore, the correct answer is false.

Explanation
The statement is false because A5 is a measurement control message used for inter-RAT (Radio Access Technology) handover, not for inter-frequency handover. Inter-frequency handover is performed within the same RAT, and different measurement control messages are used for that purpose. Therefore, A5 cannot be used in any inter-freq scenario.

Explanation
In LTE, the neighbor cell list (NCL) is not required to be sent in the measurement control message. However, the eNB still needs to create the NCL and neighbor relation table (NRT) in order to make handover decisions. This means that even though the NCL is not directly sent to the UE, it is still necessary for the eNB to have this information in order to manage handovers effectively. Therefore, the statement is true.

Explanation
In intra-freq handover, the A3Off parameter determines the threshold at which the handover decision is made. By decreasing A3Off, the threshold is lowered, allowing the handover to be initiated earlier. This ensures that the handover is done in time before the serving cell's quality deteriorates. Therefore, decreasing A3Off is the correct option to ensure timely handover and maintain quality.

Explanation
Increasing the hysteresis (Hyst) value in intra-freq handover helps to reduce the problem caused by signal fluctuations and frequent entering and leaving of the A3 condition. By increasing the hysteresis, the handover decision is delayed, and the signal must be more stable before triggering a handover. This prevents unnecessary handovers due to temporary signal fluctuations, improving the overall handover performance.

Explanation
Increasing the time-to-trigger in A3 helps prevent signal fluctuation and the ping-pong problem, where the UE enters and leaves A3 frequently. However, this can lead to a delay in handover.

Explanation
RRC Connection Reestablishment is not performed when a handover fails. Instead, when a handover fails, RRC Connection Reestablishment is not triggered, and the UE (User Equipment) remains connected to the source cell. This means that the handover failure may still cause a drop call. Therefore, the given statement is false.

Explanation
The explanation for the given correct answer, which is False, is that blind handover actually refers to a handover process where measurements are not performed by the user equipment (UE) before initiating the handover. This means that the UE does not have information about the quality of the neighboring cells before switching to them. While blind handover can result in a faster handover process, it also increases the risk of handover failure since the UE does not have the necessary information to make an informed decision about the best cell to handover to.

Explanation
The statement is false because in order to trigger coverage-based inter-freq handover faster using A4, both the parameters related to A4 and the order event parameters need to be adjusted.