The vision of the wireless communications beyond 3G is characterized by flexibility. Future communication networks should be able to flexibly allocate resources and radio access technologies (RATs) to maintain high quality of communication and efficient use of radio resources. This should be the task of the joint radio resource management (JRRM) algorithms. Furthermore, this flexibility should also cover the pricing mechanism which should be able to react to the instantaneous users' needs and resource availability. This are tackled by a real time spectrum auction system. This paper draws an architecture which embodies the two mechanisms: JRRM and spectrum auction, in order to create highly efficient wireless systems

Spectrum for mobile networks is becoming scarce and on the other hand plenty of sporadically used frequencies exist. The spectrum utilization of such spectra is very low, which is a reason to think about a way to make them available for commercial purpose without a drawback for the license owners. We recommend a strategy called spectrum pooling which is based on this idea. The notion spectrum pool was first mentioned by Mitola III (see Proc. IEEE International Workshop on Mobile Multimedia Communications, p.3-10, 1999). In a spectrum pooling system the license owner of the spectrum allows priorly specified candidate renters to use his spectrum until he needs his spectrum himself. The renters of the spectrum may be treated in two different ways. One way is that communication processes of spectrum renters can persist as long as there are channels for the processes of the license owners. The other way is that the owner has no knowledge whether the channels are occupied by renters or not and treat the channels used by renters like free channels. In both cases the renters have to measure the interference level in the channel after dedicated time intervals and have to leave the channel within the time interval T/sub p/ as soon as the interference exceeds a prior specified threshold. We compare the spectrum utilization, blocking probability and forced termination probability for these two different channel access schemes.

The demand for ubiquitous communications necessitates the development of wireless communication systems, which are able to offer high bandwidths for different types of traffic. The technological developments allow sophisticated and flexible systems with 'anywhere, anytime' capabilities. The bottleneck of such systems is the electromagnetic spectrum, which is scarce in nature. Measurements campaigns show that large parts of the licensed spectrum are not exploited or not utilized very efficiently. A dynamic frequency sharing strategy would allow systems with different radio access technologies (RAT) to use the same part of the spectrum. In this paper we describe and analyze two systems with different RATs, which share the same spectrum. In our approach, frequencies belonging to different RATs are gathered in a spectrum pool without restrictions of the availability of the spectra for their owners and are shared according to a strategy to which we further refer as spectrum pooling (SP) [F. Capar, et al., 2002], [F. Capar, et al., June 2002] and [T. Weiss, et al., June 2003]. The spectrum pooling system has access to all frequencies within the pool and is allowed to access frequencies, which are not used by the licensee. After the licensee accesses frequencies, which are used by the SP system, the SP system has to release the frequencies, which are affected. We develop a simulation model to capture the characteristics of such a system.

Software Defined Radio (SDR) technology enables a programmable radio platform that can serve as a multimode transceiver. One such example of SDR is the HackRF One, which covers the frequency of 30 MHz – 6 GHz and can be programmed as an FM receiver/transmitter, a GSM receiver, or a simple spectrum analyzer. Compared to an expensive spectrum analyzer, the HackRF One provides an affordable solution for education and simple research projects. We compare the measurement of HackRF One with a spectrum analyzer and found that spurious signals were seen with HackRF One due to the mixing and down-conversion process. However, such imperfections may offer opportunities for hands-on learning and deeper understanding of the radio signal processing. Due to its half-duplex operation, HackRF One cannot be used as a GSM BTS. However, it can still function as a GSM signal sniffer. The flexibility and programmability of SDR provide an ideal platform for project-based learning in telecommunication engineering.

Indonesia is a highly religious country, and is therefore a fertile ground for studies on religiousness. There are six religions that are endorsed by the government. Therefore, a well validated scale that can be used on those six religions are a necessity. Unfortunately, only a few studies have verified the factorial structure of such scale. The Four Basic Dimensions of Religiousness (4-BDRS), a new multidimensional scale, shows a factorial structure that has been confirmed in several countries across different religions. The current study aimed to confirm the factorial structure of 4-BDRS and its measurement invariance across genders among Muslim and Christian college students in Indonesia (two major religions in Indonesia). Data were collected from 949 college students from nine universities in the Jakarta Metropolitan area. A confirmatory factor analysis supported the four factors model of the 4-BDRS in the Indonesian context. The result of measurement invariance shows that there are configural, metric, and scalar invariances. Gender comparison showed that Muslim males had higher scores on all four dimensions of religiousness compared with females, while for Christians, there were no gender differences. The 4BDRS appears to be a valid scale to measure religiousness among Muslims and Christians in Indonesia.

The role and mechanism that religion plays in an individual’s life as suggested by many international studies might be substantially different with the one practiced in Indonesia. Studies in the Un...