Abstract The usage-based approach to first language acquisition has become highly influential in research on acquisition. In recent research, it also been adapted account for contact phenomena multilingual acquisition, i.e. situations which children acquire two or more languages simultaneously. this paper, we give a brief overview over these developments, summarize some major results of program...

The AOCMF Classification Group developed a hierarchical three-level craniomaxillofacial (CMF) classification system with increasing level of complexity and details. The basic level 1 system differentiates fracture location in the mandible (code 91), midface (code 92), skull base (code 93), and cranial vault (code 94); the levels 2 and 3 focus on defining fracture location and morphology within ...

The initial search procedure in WCDMA is used to identify the scrambling code used by the base station that has the lowest path loss coefficient of the received signal among all the other base stations. The timing relationship between base stations is asynchronous in WCDMA system. So the three-step cell search algorithm is introduced in 3GPP protocols in order to fast identify the special base ...

We consider a quasi-synchronous code-division multiple access (QS-CDMA) cellular system, where the code delay uncertainty at the base station is limited to a small number of chips. For such QS-CDMA systems, the need for code acquisition is eliminated, however, the residual code tracking and channel estimation problems still have to be solved. An extended Kalman filter (EKF) is employed to track...

Over the past year, the GPS Military Signal Design Team (GMSDT), led by the GPS Joint Program Office (JPO), has produced a recommended design of the new military signal for the L1 and L2 bands. This paper synopsizes the resulting M code signal design, which is to be implemented in modernized satellites and in a new generation of receivers. The paper summarizes the history that led to GPS Modern...

W-CDMA and SW-CDMA air interfaces are based on code division multiple access and as in all spread spectrum systems the initial acquisition procedure is a challenging issue. This procedure is identified as cell search in W-CDMA and beam search in SWCDMA. Although the terrestrial air interface W-CDMA and the satellite one SW-CDMA are very similar, the suggested cell/beam search procedures are dif...

| Suboptimal parallel schemes for the acquisition of spreading sequences in chip-asynchronous spread-spectrum systems are considered. These acquisition schemes estimate the unknown delay of the received signal with respect to a locally generated spreading code. Two schemes are presented which are considerably simpler to implement than the optimal estimator. An analytical expression is given for...

For the objective of essentially decreasing computational complexity and time consumption of signal acquisition, this paper explores a resampling strategy and variable circular correlation time strategy specific to broadband multi-frequency GNSS receivers. In broadband GNSS receivers, the resampling strategy is established to work on conventional acquisition algorithms by resampling the main lo...

In this paper, we propose a method for timing acquisition in a code division multiple access (CDMA) system. The assumptions made are that the data signals corresponding to different users are independent, and that a minor pilot sequence corresponding to the desired user is available. An independent component analysis (ICA) approach based on a fast fixed-point algorithm is used for simultaneous ...