- EI核心期刊
In order to evaluate the matching ability of the reference map in a map-matching aided navigation system, both of the sampling cycle and measurement precision of the onboard data collection system were introduced in the statistic parameters. Experiments of navigation precision have been done by numerical simulation. A recursive algorithm is adopted as the map-matching algorithm in the simulation. The relationships between the new parameters and map-matching ability were found based on the simulation results.
Let n be a positive integer, q a power of the prime p, K=Fq the finite field with q elements and F=Fqn the n-th extension of K,β a primitive element of K. It is proved that the primitive elements of F in N-1F/K(β) is uniformly distributied. Where N-1F/K(β) is the inverse function of the norm function NF/K(α) of α over K.This result isuseful in the elliptic curves public-key cryptic system.
A nov el method is proposed for the fo rw ard cov erag e ana lysis o f code divi sion mul tiple access ( CDM A) sy stems wi th heterogeneo us services, w hich is based o n a g eog raphic informa tion system ( GIS) plat fo rm. Acco rding to Mo nte Carlo simulatio n, the new method get s the fo rwa rd cov erage ranges o f the w hole analy zed area throug h analyzing the interferences in the sy stem.
A dynamic two-stage game model with spatial differentiation is proposed for products with incomplete homogenous. It is proved that the optimal strategy, in the duopoly market with unequal gross utilities derived from incomplete homogenous products, is neither maximum nor minimum differentiation, if the transportation cost is linear and the customer is uniformly distributed. The players are suggested to choose moderate spatial differentiation strategy, because the minimum differentiation will result in intensive price struggle and maximum differentiation strategy will cost resource. The other problems investigated here include transportation fee balance, monopoly pricing and collusion.
A quantum two-party authentication protocol based on entanglement swapping is proposed. This protocol is extended to a multi-party authentication protocol. In the protocols, the previously shared entangled pairs by users act as the authentication keys. The authentication among the users are realized by performing entanglement swapping on the shared entangled particles and by performing the classical communication. The security of the protocols is discussed respectively.
Mathematical analysis and comparison are made amonghigh speed optical modulation formats using LiNbO3 optical waveguide modulators. The results indicate that the NRZ (non return-to-zero) format with compactmodulation bandwidth and simple configuration seems to be desirable in the highbit rate and short/medium distance optical fiber transmission. On the other hand, the CSRZ-DPSK (differential-phase-shift-keyed carrier-suppressed return-to-zero) format with better modulation spectrum, high dispersion and nonlinearity tolerance and moderate cost is shown to be one of the best choices for thehigh bitrate and long haul optical fiber transmission.
A novel solution, which can provide integrated mobile number portability (MNP) over global system for mobile communications (GSM) and code division multipleaccess (CDMA) networks, is proposed based on both “customized application for mobile network enhanced logic(CAMEL)” and“wireless intelligent network(WIN)” technologies. The interface protocols and signaling flows are designed in details. Avoiding drastic alteration to existing networks, this solution can implement number portability over heterogeneous networks with low cost and fast speed.
The performance of multi-user diversity gain (MDG) multiple input-multiple output (MIMO) fading channels is studied by the theoryof the order statistics and random matrices. It is found that the MDG decreases with the increase of the number of antennas. It is also pointed out that the total gain, which includes the MDG and spatial multiplexing gain (SMG), must be optimized when designing the multiuser MIMO communication systems.