Fiber Distributed Data Interface (FDDI) is a 100 megabits per second ber optic local area network (LAN) standard being developed by the American National Standard Institute (ANSI). We analyze the impact of various design decisions on the error detection capability of the protocol. In particular, we quantify frame error rate, token loss rate, and undetected error rate. Several characteristics of...

Abstmct-The channel code decoder in a CDMA mobile not accounted for the non-stationary in-cell interference performs channel state estimation to determine the reli-that occuTs on a CDMA fonvard link using concatenated WalshjPN sequence spreading. CDMA forward link chan-ability of each received encoded symbol. This reliability information is typically an estimate of received signal envelope and ...

Adaptive Array, with spatial processing, used in CDMA multiuser communications can enhance range, reliability and capacity. Moreover, the adaptive beamforming technologies can remove unwanted noise and interference from the received signal. In this paper, we propose four adaptive antenna receiver structures for DS/CDMA multiuser environment with multipath fading channels. LMS and RLS algorithms...

Owing to frequency diversity gain and simplicity, a chip interleaved multi-carrier code division multiple access (MC-CDMA) system has been considered in a multi-cell environment, and combining it with multiple input multiple output (MIMO) schemes offers high spectral efficiency. In spite of the advantages, the system is highly affected by inter code interferences. To control them, this letter a...

A uniformly distributed hopping code (UDHC) suitable for M-levelled M-ary Frequency Shift Keying (MMFSK) and Multi-tone MMFSK (MFSK) modulation schemes is introduced. The proposed code is designed with the requirements that it utilises all the available frequencies within the symbol period and that it is uniformly distributed, thereby making it efficient in terms of spectral usage and also easi...

Fix a random variable X having as its possible values entries of a set X . Let Σ∗ denote the set of strings whose characters are taken from an alphabet Σ. In the case Σ has two elements, we can interpret elements of Σ∗ as bit strings, for example. Let Y denote a set of target symbols and C denote a code, a function of the form X → Y∗. The extension of a symbol code, a code of the form C : X → Y...

We describe the effect of a particular form of “noise” in benchmarking. We investigate the source of anomalous measurement data in a series of optimization strategies that attempt to improve data cache performance in the garbage collector of a Java virtual machine. The results of our experiments can be explained in terms of the difference in code positioning, and hence instruction and data cach...

in this paper, we propose space-time block codes based on constituent intersectant orthogonal designs. after channel model is formulated, we studied the space-time block codes from constituent intersectant orthogonal designs. at last we made simulations for the space-time block codes from complex orthogonal design and the space-time block codes from constituent intersectant orthogonal design to...

Conventional trellis coding outputs one channel symbol per trellis branch. channel symbol combination of performance ga Here we introduce the notion of multiple trellis coding wherein more than one the a per trellis branch is transmitted. It is shown that multiple trellis coding with M-ary modulation yields n with symmetric signal sets comparable to that prev ously achieved only with signal con...