摘要:
A mobile communication system includes a first and second systems. Each of the first and second systems has a land station and at least one mobile terminal capable of communicating with the land station. The land station of the first system has a broadcasting channel transmission unit for transmitting status information via a broadcasting channel, and the mobile terminal of the second system has a broadcasting channel receiving unit for receiving information in the broadcasting channel to obtain a broadcasting channel receiving condition and the status information, a giving interference estimation unit for estimating giving interference level onto communication of the first system by the second system based upon the obtained broadcasting channel receiving condition and the obtained status information, and an output signal level control unit for controlling output signal level of the mobile terminal of the second system based upon the estimated giving interference level.
摘要:
In the preliminary authentication stage, the mobile station (35) is authenticated by sending from the home network (30) to the roamed network (31), a plurality of pairs of first random numbers (RNDa.sub.1, . . . , RNDa.sub.n) and calculation results (SRESa.sub.1, . . . , SRESa.sub.n) of the cipher function (f), which calculation is performed at the home network using the secret key (ki) and the first random numbers (RNDa.sub.1, . . . , RND.sub.an), by sending, from the roamed network to the mobile station, third random numbers formed by coupling second random numbers (RNDb.sub.1, . . . , RNDb.sub.m) produced at the roamed network with the first random numbers (RNDa.sub.1, . . . , RNDan), by sending, from the mobile station to the roamed network, calculation results (SRESa.sub.1, . . . , SRESa.sub.n, SRESb.sub.1, . . . , SRESb.sub.m)) of the cipher function (f), which calculation is performed at the mobile station using the secret key (ki) and the sent third random numbers, and by confirming, at the roamed network, coincidence of the calculation results (SRESa.sub.1, . . . , SRESa.sub.n) sent from the mobile station with the calculation results (SRESa.sub.1, . . . , SRESa.sub.n) sent from the home network. In the main authentication, the mobile station is authenticated by using a pair of the second random number (RNDb.sub.1, . . . , RNDb.sub.m) and of the calculation result (SRESb.sub.1, . . . , SRESb.sub.m) with respect to the second random number (RNDb.sub.1, . . . , RNDb.sub.m), sent from the mobile station.
摘要:
A mobile communication system includes a plurality of antennas for sending and receiving beams, a plurality of mobile terminals moving in a fixed direction substantially, and a zone-shift control unit for treating the moving mobile terminals locating within a predetermined area as a single moving zone and for controlling the antennas and directions of the beams so that the beams always cover the moving zone.
摘要:
In order to prevent decrease of channel efficiency and to effectuate high quality communication while moderating increase of apparatus scale of an interference canceler part and cutting down costs, in a mobile communication and radio base station apparatus according to the present invention, an interference cancel processing part within the base station apparatus is provided with reverse spread processing/respread processing parts for performing reverse spread processing and respread processing on received signals, synthesizing processing parts for synthesizing signals that have been subjected to the respread processing, and subtraction processing parts for subtracting the synthesized signal from received signal, in multiple stages. The interference cancel processing part processes received signals of users #1-#k. As a demodulation processing part, there is provided n demodulation processing parts that perform demodulation processing for received signals of users #1-#n, the number of those users being larger than the number of the users that can be processed in the interference cancel processing part. Those demodulation processing parts perform demodulation processing with respect to signals that have been subjected to the interference cancel processing.
摘要:
This invention provides a spread spectrum signal demodulator in which a noise component included in respective demodulation symbols is reduced and an effect of interference removal is further improved. Symbol decorrelating means detect correlations between spread codes allocated to spread spectrum signals to be removed and a receiving signal. A symbol deciding means 121 synthesizes one or the plurality of one symbol correlation values b1 to bk in common phase, namely, diversity-synthesizes them so as to decide a symbol. As the symbol decision, hard decision or soft decision can be used. Correlation modification means input the one symbol correlation values b1 to bk output from the symbol decorrelating means and the symbol decided result output from the symbol deciding means 121 thereinto, and modify the symbol correlation values b1 to bk. The modified symbol correlation values d1 to dk are transmitted into interference replicating means so as to be spectrum-spread by corresponding spread codes.
摘要:
A base station apparatus, a mobile radio system, and a transmission power control method that can perform transmission power control having the high interference suppressing effect with a smaller processing delay are provided. The base station apparatus comprises: a measurement part for measuring SIRs of a received signal subjected to interference suppression by an interference suppressing receiving circuit in a former stage in an interference suppressing receiving part of the radio base station apparatus, and of a received signal subjected to interference suppression by an interference suppressing receiving circuit in a later stage; a calculation part for calculating a correction SIR based on the obtained SIRs, and for estimating a transmission power control SIR from a current first stage SIR and a past correction SIR; and a signal generator for generating a transmission power control signal by comparing the transmission power control SIR and a target SIR. Control of transmission power of a mobile station is performed by transmitting this transmission power control signal to the mobile station.
摘要:
A method of transmitting adaptive modulation signals using space-time block code matrix from a plurality of antennas, the method comprising the steps of: changing adaptively the number of transmission repeat times of the matrix according to a propagation condition, transforming modulation signals at each transmission repeat timing from each antenna by using the matrix, and sending the transformed signals at each transmission repeat timing from each antenna.
摘要:
A control method of transmitting power in a cellular system includes a step of measuring a signal to interference power ratio of a received signal at said receiving side, a step of detecting frame errors of the received signal at the receiving side, a step of counting the number of the detected frame errors n(k) (k and n(k) are positive integers and 1≦k≦K) for every M(k) (M(k) is a positive integer) frames, or for last N(k) (N(k) is a positive integer) frames just before the frame error is detected, a step of adjusting a value of a target SIR depending on one or set of the counted numbers of frame error n(1) to n(K), a step of comparing the measured SIR with the adjusted target SIR to provide a compared result, and a step of controlling at the transmitting side the transmitting power depending on the compared result.
摘要翻译:在蜂窝系统中发送功率的控制方法包括测量所述接收侧的接收信号的信号与干扰功率比的步骤,检测接收侧的接收信号的帧错误的步骤, 对于每个M(k)(M(k)是正整数)帧,检测到的帧错误n(k)(k和n(k))是正整数,并且1 <= k <= K) 在检测到帧错误之前的N(k)(N(k)是正整数)帧;根据帧错误n(1)的计数数目的一个或一组来调整目标SIR的值的步骤 n(K),将测量的SIR与调整后的目标SIR进行比较以提供比较结果的步骤,以及根据比较结果在发送侧控制发送功率的步骤。
摘要:
A spread spectrum signal demodulator receives a received signal including a plurality of spread spectrum signals, and comprises at least one signal strength suppressing means, which reduces a correlation signal outputted from a first correlation detecting means or replica signals until the correlation signal has been traveled through a replica signal generating means, a replica signal subtracting means and a second correlation detecting means. According to the invention, it is possible to improve interference cancellation capacity with a computational effort substantially comparable to that in a prior art replica signal cancellation system and improve interference cancellation performance with increasing number of interference cancellers irrespective of the magnitude of the correlation. With a sufficient number of interference cancellers provided, it is possible to obtain the same effect as obtainable with prior art decorrelation in a real time processing irrespective of the correlation magnitude.
摘要:
A demodulator receiving as input signal a sum of a plurality of spread spectrum signals is disclosed. The demodulator comprises means for obtaining a correlation between a spreading code assigned to each of spread spectrum signals contained in the input signal and the input signal for each spread spectrum signal symbol and making the correlation thus obtained to be a 0-th detected correlation, a 1-st interference canceller stage for receiving as inputs the input signal and the 0-th detected correlation and outputting 1-st residual error signal, 1-st detected correlation and sum of the 0-th and 1-st detected correlations, and a plurality of interference canceller stages operable similarly to the 1-st interference canceller stage by receiving as input the output signal of the preceding interference canceller stage.