Abstract: An apparatus for estimating a plurality of channels from a plurality of distinct transmitting points, wherein an input signal includes a super position of signals based on a first pilot sequence transmittable from a first transmitting point and on a second pilot sequence transmittable from a second transmitting point, the first pilot sequence and the second pilot sequence having a phase shift to each other, comprises a transformer, which is operative to translate phase shifts between the first and the second pilot sequence into a delay, so that a first group of a set of discrete values of the transformed signal includes channel information of a first channel and that a second group of a set of discrete values includes channel information of a second channel, a selector for selecting the first group from the set of discrete values and for selecting the second group from the set of discrete values to obtain selected groups, and means for determining channel information for the plurality of channels based on the

Abstract: The present invention achieves differential transmit diversity and related diversity reception schemes transmit symbol constellations which are extended to multiple levels. Heretofore, a group of transmission bits is divided into a first sub-group of transmission bits and a second sub-group of transmission bits. Then, the first sub-group of transmission bits is mapped (14) onto constellation points of a differential transmit diversity coding scheme from an orthogonal design for coding of the first sub-group of transmission bits. Then, after differential encoding of the constellation points (32, 34, 36, 40) a length of the transmission symbol vector is scaled (38) for coding the second sub-group of transmission bits. Therefore, the present invention overcomes restrictions implied through unit length requirements for previously known differential transmit diversity schemes from orthogonal designs.