1 CDMA Concept 4 1.1 Basic Principles of Spread Spectrum . . . . . . . . . . . . . . . . . . . . . . . . . 4 1.1.1 Direct Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 1.1.2 Frequency Hopping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 1.1.3 Time Hopper . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 1.1.4 Hybrid Systems . ....

Ultra-WideBand (UWB) has been recently presented as a promising radio technology due to the large bandwidth available. This feature enables point to point high data rates at short range as well as high temporal resolution with long channel impulse reponses (CIR). In this paper, we present an original multiple access scheme called Channel Division Multiple Access (ChDMA), where we use the CIR as...

This study extends the analysis in [1] where the effect of the round trip propagation delay on performance measures of an Asynchronous Transmission WDMA protocol is examined for infinite population and Poisson arrivals. An other attribute, associated with the WDM networks, that affects their behaviour is the receiver collision phenomenon. Especially this paper examines the influence on throughp...

We demonstrate the feasibility of a 16 × 3.75 Gb/s (60 Gb/s aggregate) Orthogonal frequency division multiplexing-code division multiple access passive optical network for next-generation access applications. 3.75 Gb/s PON channel transmission over 25 km single-mode fiber shows 0.1 dB dispersion and 0.9 dB crosstalk penalties. Advantages of the system include high capacity, enhanced spectral ef...

Fabry-Perot Filters are major candidates for use as demultiplexers in wavelength division multiple access networks. In this paper we investigate the crosstalk limitations of such filters, compare their performances, and optimize the filter design to minimize the crosstalk degradation.

-In this paper we study the effect of round trip propagation delay in performance measures of Wavelength Division Multiplexing (WDM) networks. Even though the impact of propagation delay is substantial in optical networks behavior, most of the studies ignore the effect of this object in throughput and delay evaluation. We assume a WDM Local Area Network (LAN) where the round trip propagation de...

The traffic flow in long-haul dense wavelength division multiplexing fiber networks has surpassed by far the traffic deliverability from/to the access network thus creating what is known as “access bottleneck”. This bottleneck was the result of two major factors, the inherent cost sensitivity of access networks that impedes deployment of new optical technology prior to cost maturity, and the la...

Efficiency and adaptivity play a major role in the design of fourth-generation wireless systems (4G). These systems should be efficient in terms of bandwidth and power allocation and will satisfy the users requirement on low power consumption, little interferences with other systems, and high rate transmission. Moreover, low complexity transceivers are expected. This paper will propose a novel ...