D spread spectrum (DSSS) and frequency-hopping spread spectrum (FHSS) technologies have different physical mechanisms for rejecting narrowband interference. Because of these physical differences, they perform differently in the presence of the same levels of narrowband interference. This is an important case for successful operation in the ISM bands. After presenting the physical mechanisms by ...

With a narrowband multiuser detector (MUD), multiple users can simultaneously share the same channel without using a bandwidth expanding signature code when sufficient power differences at the receiver are maintained. In this paper, we estimate the capacity that can be achieved in a hypothetical cellular system with centralized power control, using a narrowband MUD based on successive cancellat...

Human listeners are extraordinarily sensitive to a transient break in interaural correlation (called binaural gap). In this study, a binaural gap embedded in interaurally correlated noise markers elicited marked scalp event-related potentials (ERPs). ERPs to the binaural gap in narrowband noise with the center frequency of 1600 Hz were significantly weaker than those for narrowband noise with t...

Simplified broadband beamformers can be constructed by sharing a single tapped-delay-line within a narrowband subarray. This paper discusses the use of fractional delay filters to a steering in the digital domain. For the narrowband subarrays, an optimisation approach is proposed to maintain an off-broadside look direction constraint as best as possible across a given frequency range. We demons...

In general, narrowband systems require more complex terminals which require more space and power and are more costly than wideband terminals. Conversely, in general, wideband systems require more costly transmission facilities. Most Defense tactical users require wideband facilities at the present time due to weight, size, and power constraints. Nontactical users generally are located in an ofk...

We study singly-resonant optical parametric oscillators with chirped quasi-phasematching gratings as the gain medium, for which adiabatic optical parametric amplification has the potential to enhance conversion efficiency. This configuration, however, has a modulation instability which must be suppressed in order to yield narrowband output signal pulses. We show that high conversion efficiency ...

OBJECTIVE When assessing adult ADHD, self-report measures are commonly used to guide clinical diagnosis. Self-report measures may be broadband covering a range of behaviors or narrowband and specific to symptoms associated with ADHD. METHOD This study examined the results of broadband and narrowband measures for college students referred for evaluation of ADHD at a university clinic. RESULT...

Power patterns in the frequency domain are usually used to describe the antenna performance in narrowband communication systems; however, they are not sufficient for ultra wideband (UWB) antennas in wideband communication systems. In this paper, energy pattern and energy gain are introduced to describe the performance of UWB antennas. Numerical simulations and measurements are used to demonstra...

In this paper, together with its Part II, the impact of relaying and adaptive modulation and coding (AMC) on data throughput in narrowband wireless multi-hop networks is investigated. This part focuses on the physical layer of a single-carrier narrowband time division multiple access (TDMA) transmission in the very high frequency (VHF) band. The transmission chain is designed for a narrowband, ...