Abstract: The invention relates to a method for reducing NAS signaling of LCS and LPP procedures initiated by UE in EMM idle mode and EMM registration state. The disclosed method involves multiple methods of encapsulating LPP/LCS messages into control plane service requests. This makes it possible for the UE and eNB to transmit LPP/LCS messages during the RRC connection establishment procedure, and can be regarded as an extension of the control plane EPS CIoT optimization.

Abstract: Various solutions for handling back-off timer in session management level congestion control with respect to user equipment and network apparatus in mobile communications are described. An apparatus may establish a first connection with a first packet data network (PDN) or packet data protocol (PDP) type. The apparatus may transmit a first request message with a second PDN or PDP type for establishing a second connection. The apparatus may receive a reject message with a reject cause. The apparatus may transmit a second request message for establishing the second connection without initiating a default back-off timer.

Abstract: Various solutions for handling re-attempt indicator with respect to user equipment and network apparatus in mobile communications are described. An apparatus may receive a reject message without a back-off timer value from a network node. The apparatus may start a back-off timer by using a predetermined timer value. The apparatus may perform a re-attempt procedure according to a re-attempt indicator.

Abstract: A module and a method for estimating signal direction of arrival are disclosed. The module consists of a processing unit and a direction finder. Using spatial signatures at different carrier frequencies, the processing unit generates a generating set of a subspace. Based on the generating set, the signal subspace is extended. Then, the direction finder estimates signal direction of arrival according to the signal subspace. The module for estimating signal direction of arrival of the present invention effectively reduces wrong estimation of the signal direction of arrival caused by loss of rank.