We evaluate the performance of recently proposed dynamic frequency hopping (DFH) when applied to cellular systems with a limited total bandwidth. We also illustrate a practical implementation for DFH deployment using network-assisted resource allocation (NARA). The performance evaluation is accomplished by system-level simulations of a system with 12 carriers and 1/1 frequency reuse, based on t...

We study localization in twoand three channel quasi-1D systems using multichain tight-binding Anderson models with nearest-neighbour interchain hopping. In the three chain case we discuss both the case of freeand that of periodic boundary conditions between the chains. The finite disordered wires are connected to ideal leads and the localization length is defined from the Landauer conductance i...

Taylor and Weibel's theory of symmorphosis predicts that structures of the respiratory system are matched to maximum functional requirements with minimal excess capacity. We tested this hypothesis in the respiratory system of the migratory locust, Locusta migratoria, by comparing the aerobic capacity of the jumping muscles with the morphology of the oxygen cascade in the hopping legs using an i...

Breathing, heart and gait frequencies, tidal volume, cardiac output, and rates of oxygen consumption were measured in tammar wallabies (Macropus eugenii Desmarest) hopping on a treadmill. At speeds greater than 1.6 ms-1 the rate of metabolic power consumption was independent of hopping speeds. Blood lactate levels within the speed range where VO2 was independent of speed showed a mean increase ...

In organized beam-hopping (OBH) based systems, the organized hopping pattern is changeable according to the distribution of the mobile stations (MS) in the cell. However, the changed beam-hopping patterns may cause severe co-channel interference for the users which are hit by more than one beam. In this paper, we develop an interference situation adaptation scheme for OBH-based systems. The int...

A statistical multiplexing scheme in orthogonal downlinks is proposed to accommodate more downlink orthogonal channels than orthogonal codewords for mobile stations. The number of allocable downlink orthogonal channels depends on the average burstiness of the channels. The statistical multiplexing scheme is called here as the orthogonal code hopping multiplexing (OCHM). Since the OCHM uses a pr...

A Generalized Frequency Hopping (GFH) OFDMA system is developed in this paper as a structured long code DS-CDMA system in order to bridge frequency hopped multi-carrier transmissions with long code DS-CDMA. Through judicious code design, multiuser interference is eliminated deterministically in the presence of unknown frequency-selective multipath channels. Thanks to frequency hopping, no singl...