Resource allocation issue is studied for broadcast mode of device-to-device (D2D) communication in cellular networks. We design systematic methods for transmission sub-frame selection by broadcast UEs. Firstly, we design transmission patterns based on Hadamard matrix for the case with 8 D2D sub-frames per D2D period. Then, we expand transmission patterns to the 16 sub-frame case. Accordingly, we design a distributed scheduling scheme, which can be naturally applied with a well-designed transmission pattern set and takes into account spatial relationships between broadcast UEs. System level simulation shows the performance gain provided by the designed Hadamard-matrix-based transmission pattern set and the weighted collision minimization scheduling scheme.

To provision the enhanced support for wireless Internet services, high speed downlink packet access (HSDPA) was standardized in 3GPP. It offers peak air interface data rates of up to 14.4 Mbps with 5 Mhz bandwidth, thus dramatically improving the existing packet service capability of UMTS R99. At the same time, Evolution-Data Optimized (EV-DO) has been standardized in 3GPP2 to provide up to 4.9 Mbps throughput with 1.25 Mhz bandwidth. However, because of inter-cell interferences, users in the cell edge area generally cannot enjoy the higher data rate supported by the standard. Moreover, to meet the system fairness criterion, a base station usually needs to allocate un-proportional radio resource to these users. In this paper, we propose a simple interference mitigation scheme to enhance cell edge user data rate through network coordination. It is demonstrated through extensive simulations that the scheme significantly improves cell edge user throughput without lowering the total system capacity and spectral efficiency.

In this paper, we evaluated adaptive frame length switching algorithms for the enhanced uplink dedicated channel in UMTS. Different alternatives to achieve the frame switching are presented and discussed accompanied by results from simulated system throughput performance. Moreover, we also discussed the implementation issue associated with avoiding ping-pong effect caused by mobile movement. Dynamic system simulation was performed and it showed 10% improvement by switching between 2 ms and 10 ms TTI (frame) transport channels for EDCH with different threshold selection. The results show that the adaptive switching based on the user geometry with ping-pong avoidance has the most performance gain over fixed TTI system

In this paper, we evaluated and proposed an adaptive frame length switching for the enhanced uplink dedicated channel in UMTS. Different alternatives to achieve the frame switching are presented and discussed accompanied by results from simulated system throughput performance. The results show improvement by switching between 2 ms and 10 ms TTI transport channels for EDCH. A fixed 10 ms or 2 ms TTI transport channel structures have advantages and limitations in different areas of the radio channel conditions, scheduling strategies, and resource management. Different strategies looking to exploit the existence of a single configurable transport channel the E-DCH to perform adaptive switching is examined and results identifying the projected performance gains of a user geometry approach are presented

This paper presents the wireless intelligent ATM (WIATM) network, designed to provide wireless broadband integrated services. The WIATM network takes advantage of the ATM-cell relay paradigm for integrated services through a radio link with quality of service (QoS) guarantee. The design of the WIATM network architecture is an independent wireless network, which is consistent with the inherent cellular/PCS network architecture, as a wireless customer premises equipment/network (CPE/CPN) to access the ATM transport network in the B-ISDN infrastructure. An independent network architecture design separates the wireless access network from the ATM backbone network; this provides flexibility for wireless resource management with low rate source codecs with minimal tolerable QoS considered to increase the spectral efficiency, and mobility support by taking advantage of the functionalities of the IS-41 circuit-switching handoff procedures. The protocol design of the air interface is to meet the QoS requirements of wireless B-ISDN services and to be compatible with that of B-ISDN UNI. A hybrid concatenated error control scheme distributed through the protocol layers is used to target individual QoS requirements of different services. The convolutional coding and interleaving in the wireless physical layer protocol are used to guarantee QoS of voice services. A concatenated coding with additional 36 bit BCH code in the wireless ATM layer, which replaces the VCI/VPI of the ATM header field, improves the QoS up to the requirement of video services. The VCI/VPI field in WIATM is an overlapped routing information routing with the address control by radio port controller, and is thus not needed in the wireless ATM layer protocol. The retransmission scheme for data service only is added in the wireless data link layer, which is on top of wireless AAL, to meet its QoS requirement. Examples of signaling flows for call registration, call setup, and supporting handoff are shown in the design of the wireless network layer protocol. The AIN (advance intelligent network) signaling functionalities are considered for multimedia service control in the access network and interconnection to the ATM network. A parent-child creative basic call state model (BCSM) for wireless integrated services is introduced in both call origination and termination.