Abstract: A CDMA demodulating apparatus with an improved interference canceling effect when there are a large number of communicators. A reception signal having a frame configuration in which a pilot signal of a known pattern is inserted between information signals is received from a plurality of communicators. Transmission data of each communicator is demodulated, an interference canceler for estimating is provided in a plurality of stages, in each channel of each stage, a variation of transmission path is estimated in each path to achieve data demodulation and estimation of interference replica. The later the stage, the more error of interference signal replica can be reduced, thereby improving the interference canceling effect. An even better effect can be obtained when interference canceling is performed after detecting a reception level of each channel by summation of reception power of each path of each channel, and channel ranking is determined in the order of higher reception level.

Abstract: Enabling reception quality to be improved and the capacity in terms of the number of simultaneous users in a cell to be increased, and speeding up the establishment of spreading code synchronization and the convergence of weighted coefficients, by feedback controlling weighted coefficients such that desired signal power to interference power ratio (SIR) becomes maximum. A coherent adaptive diversity configuration is employed to which absolute coherent detection is applicable. Adaptively feeding weighted coefficients back to diversity branches makes it possible to reduce the influence of the interference power from other users, and thus to increase the capacity in terms of the number of simultaneous users in the cell. Furthermore, the direction that provides the maximum received SIR is determined while rotating antennas in a state of having directivity with a predetermined angle range.

Abstract: Datapath elements 1.sub.1 to 1.sub.N can exchange data respectively with local memories 2.sub.1 to 2.sub.N through data buses 6.sub.1 to 6.sub.N, so that parallel operations can be performed. The data bus 6.sub.1, which is connected with one datapath element 1.sub.1, can be connected with the other data buses 6.sub.2 to 6.sub.N through an interconnection network 5, so that by activating one datapath element 1.sub.1 only, data exchange can be made with all of the local memories 2.sub.1 to 2.sub.N through the data buses 6.sub.1 to 6.sub.N and the interconnection network 5. Thus, the multiple datapath elements can perform the parallel operations with being related with the multiple local memories: and a simple configuration is employed such that one datapath element can access to any one of the local memories.

Abstract: A minimum/maximum data detector for rapidly detecting the minimum or the maximum data from a plurality of numeric data. In FIG. 1 , one of consecutive numeric data stored in memory 1 is read out by an address designated by a register 2, and is transferred to registers 5 and 6. A counter 9 counts up the number of numeric data which have been stored in register 6. The contents of the registers 5 and 11 are compared by a circuit 4. When detecting minimum data, if the contents of the register 5 are judged to be smaller, the contents of the register 6 and the counted results of the counter 9 are linked in an index linking circuit 10. The linked result is then stored in the specific register 11. The content of the register 2 is incremented by "1" whenever the comparison is executed. Once the read out of one series of consecutive numeric data have been completed, then the numeric data remaining in the specific register 11 is the minimum data.

Abstract: A CDMA receiver capable of effective orthogonalization even when the number of received signal vectors to be orthogonalized is very large. Received signals which have been spread by spreading codes are despread by despreading filters. Products of received signal levels and cross-correlations between the spreading codes are compared in a preliminary selector of the cross-correlations, and Ns products are selected in order of magnitude, where Ns is a predetermined integer. Ns received signals associated with the selected products have priority to undergo orthogonalization. The number of signals to be orthogonalized by decorrelators can be effectively decreased, and noise enhancement effect can be reduced on the reverse channels. The orthogonalized received signals are recovered through channel estimators, phase compensators, RAKE combiners and decision blocks.

Abstract: A determinant, which represents the relationship between a sequence of code division multiplexed transmission symbol vectors b(k) from L communicators and a sequence of despread output vectors y(k) of received signals taking into account the cross correlation between spreading code sequences of transmitted signals, is limited within the range of .+-.g symbol duration about symbol timing k, and despread outputs of received signals within the limited range are inputted into a 2g+1-stage shift register. On the other hand, partial correlation matrixes R.sup.k+h (1), R.sup.k+h (0) and R.sup.k+h (-1) for each symbol duration within the limited range are calculated by a partial correlation computing part with respect to h=-g, . . . , g, then a correlation matrix R.sup.k between the spreading code sequences corresponding to the L communicators is derived from the partial correlation matrixes in an inverse matrix computing part and an inverse correlation matrix R.sub.k.sup.-1 of the correlation matrix is calculated.