This paper provides network designers and operators with simple guidelines on traffic measurements and efficiency evaluation of various channel allocation schemes in digital mobile telecommunications networks. The paper evaluates the efficiency obtained by implementing the following channel allocation schemes: 1) fixed uniform channel allocation (FUCA); 2) fixed nonuniform channel allocation (F...

The MC-CDMA transmission technique is seen as a candidate for beyond 3G systems. It benefits from the high bandwidth efficiency of multi-carrier systems and the flexibility and granularity offered by CDMA for resources allocation. In the framework of the IST MATRICE European project, a MC-CDMA beyond 3G system has been defined and extensively studied. This paper describes the sensitivity of thi...

As is well known, the frequency allocation problem for mobile telephone networks can be approximated by a graph coloring problem where vertices model transmitters, colors model frequencies, and an edge corresponds to a pair of transmitters that must not use the same frequency. However, the graph coloring analogy doesn't suuce for modeling real world problems , which involve soft constraints and...

Frequency domain experiments are efficient screening procedures for identifying important factors in simulation models. An empirical investigation involving a simple autoregressive system and a complex queueing system shows that allocating data unequally among signal and noise runs may be more effective when the data collection effort is limited.

The evolution of Mobile Internet has led to the growth of bandwidth demanding applications like video streaming and social networking. The required data rates projected for such applications cannot be sustained by current cellular networks. New network architectures like Long Term Evolution (LTE) and LTE Advanced have been carefully engineered and introduced to fulfill such large data rates. Th...

We consider a network model where the nodes are grouped into a number of clusters and propose a distributed dynamic frequency allocation algorithm that achieves performance close to that of a centralized optimal algorithm. Each cluster chooses its transmission frequency band based on its knowledge of the interference that it experiences. The convergence of the proposed distributed algorithm to ...

We study the online frequency allocation problem for wireless linear (highway) cellular networks, where the geographical coverage area is divided into cells aligned in a line. Calls arrive over time and are served by assigning frequencies to them, and no two calls emanating from the same cell or neighboring cells are assigned the same frequency. The objective is to minimize the span of frequenc...

Abstract— Orthogonal frequency division multiplexing (OFDM) is an important technique to support high speed transmission of broadband traffic in wireless networks, especially broadband wireless local area networks (LANs). Based on OFDM, a new multiple access scheme, called OFDM-TDMA with subcarrier allocation (OFDMTDMA/SA), is introduced in this paper. It provides more flexibility in resource a...

A closed-loop MIMO-OFDM transmitter can exploit channel knowledge using eigenbeamforming to create MN parallel channels, where M is the number of antennas at both ends and N is the number of OFDM tones. We find that the penalty due to a flat-frequency constraint, which forces each tone to convey the same amount of information, becomes negligible as M grows. We propose low-complexity bit-allocat...

The online frequency allocation problem for cellular networks has been well studied in these years. Given a mobile telephone network, whose geographical coverage area is divided into cells, phone calls are served by assigning frequencies to them, and no two calls emanating from the same or neighboring cells are assigned the same frequency. Assuming an online setting that the calls arrive one by...