The problem under consideration is the adaptive reception of a multipath direct-sequence spread-spectrum (SS) signal in the presence of unknown correlated SS interference and additi ve impulsive noise. An SS receiver structure is proposed that consists of a vector of adaptive chip-based Hampel nonlinearities f ollowed by an adaptive auxiliary-vector linear tap-weight filter. The nonlinear recei...

The study about the swarm-robot system is one of the most important directions of multitudinous robots system. It is an extraordinary challenged issue which how to communicate with each swarm-robot to cooperate together to accomplish a mission in numerous units. The swarm-robot system, which is based on CC2510 wireless sensor network, with the Radio Frequency of FHSS as the communication mode, ...

For various quasisynchronous (QS) CDMA systems such as LAS-CDMA system which emerged recently, in order to reduce or eliminate the multiple access interference and multipath interference, it is required to design a set of spreading sequences which are mutually orthogonal within a designed shift zone, called orthogonal zone. For traditional orthogonal sequences, such as Walsh sequences and ortho...

We study the effect of interference on the performance of coded FHSS systems. This is achieved by modeling the physical channel in these systems as a block fading channel. In the derivation of the bit error probability over Nakagami fading channels, we use the exact statistics of the multiple access interference (MAI) in FHSS systems. Due to the mathematically intractable expression of the Rici...

Ultra-wideband radio systems operate using extremely short duration signaling pulses. Spread spectrum techniques for multiple access and interference suppression are commonly considered for such systems. We compare time-hopping spread spectrum with pulse position modulation (TH-PPM) and timehopping/direct-sequence spreading with antipodal signaling (TH/DS-BPSK) in terms of their multiple access...

Recently, ultra-wideband (UWB) technology, which uses a very short pulse for wireless digital communications, has been extensively investigated due to its significance that enables to transmit data sequences at a very high rate. Although the propagation range of UWB signals is short (about ten meters [1]), its impact on wireless home networks can be quite significant. Apart from the support of ...

In this paper, the effect of co-channeled Bluetooth (BT) piconets on a carrier sense multiple access (CSMA)-based wireless local area network (WLAN) is investigated. Specifically, the p-persistent CSMA protocol is considered for WLAN and the probability of error of a WLAN packet is calculated in the presence of interfering BT packets of different lengths, variable piconet traffic loads, and as ...

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 ...

We describe a transmission scheme combining 4-FSK modulation with diversi&'&d coding to make the transmission over power lines robust against permanent frequency disturbances and impulse noise. We use simple non-coherent detection and derive the corresponding error correcting capabilities of the scheme. Since we use 4-FSK, the scheme is in agreement with the existing CENELEC norms. The scheme c...

Several studies have highlighted that the IEEE 802.15.4 standard presents a number of limitations such as low reliability, unbounded packet delays and no protection against interference/fading, that prevent its adoption in applications with stringent requirements in terms of reliability and latency. Recently, the IEEE has released the 802.15.4e amendment that introduces a number of enhancements...