A terminal apparatus includes circuitry and a transmitter. The circuitry, in operation, generates a reference signal using a cyclic shift value and an orthogonal sequence, which are associated with each other. The orthogonal sequence is one of two orthogonal sequences corresponding to a first orthogonal sequence [1, 1] and a second orthogonal sequence [1, 1]. The cyclic shift value is one of 12 cyclic shift values ranging from 0 to 11. The transmitter, in operation, transmits the reference signal multiplexed with a data signal. Two of the cyclic shift values having a difference of 6 are respectively associated with the two orthogonal sequences.

Systems and methods for calibrating a phase array antenna (PAA) are provided. The system includes a PAA having a plurality of array elements and a remote calibration terminal. The PAA is connected to a processor unit. The PAA includes a reference beamforming network (BFN) for generating a reference beam and a calibration BFN for generating a calibration beam. The PAA applies a plurality of scrambled orthogonal codes to the calibration BFN to generate the calibration beam. The remote calibration terminal is configured to analyze the reference beam and the calibration beam to determine a calibration error for the PAA, the calibration error including a phase error and an amplitude error for each of the plurality of array elements of the PAA. The remote calibration terminal may be configured to measure a beam pointing error (BPE) of the PAA and/or a coupling between array elements.

A transmitting device includes: a compressing unit configured to generate and output a compressed digital signal that has been compressed, by converting an input digital signal by use of a Walsh function and extracting a specific frequency component.

A terminal apparatus is disclosed wherein even in a case of applying SU-MIMO and MU-MIMO at the same time, the inter-sequence interference in a plurality of pilot signals used by the same terminal can be suppressed to a low value, while the inter-sequence interference in pilot signal between terminals can be reduced. In this terminal apparatus: a pilot information deciding unit decides, based on allocation control information, Walsh sequences of the respective ones of first and second stream groups at least one of which includes a plurality of streams; and a pilot signal generating unit forms a transport signal by using the decided Walsh sequences to spread the streams included in the first and second stream groups. During this, Walsh sequences orthogonal to each other are established in the first and second stream groups, and users are allocated on a stream group-by-stream group basis.

A base station which performs Multiple Input Multiple Output (MIMO) transmission. A processor configured to generate reference signals by spreading with four groups of orthogonal code sequences, each group of orthogonal code sequences including four orthogonal sequences, wherein the orthogonal code sequences correspond to transmission layers and each of the orthogonal code sequences has a length of four, and a transmit circuit configured to transmit the reference signals. The four groups include a first group where the orthogonal code sequences are Walsh code sequences, a second group where the orthogonal code sequences are represented by mirroring of the orthogonal code sequences in the first group, a third group where the orthogonal code sequences are represented by cyclic shifts of the orthogonal code sequences in the first group, a fourth group where the orthogonal code sequences are represented by mirroring of the orthogonal code sequences in the third group.

A cellular communication system comprising a plurality of geographically spaced base stations (2) each of which comprises an antenna arrangement (4, 6, 8) per base station sector, each of which antenna arrangements has an antenna element for generating an array of narrow beams (10, 12, 14) covering the sector. Timeslots are simultaneously transmitted over each of the beams so as to generate successive sets of simultaneously transmitted timeslots per sector. The timeslots are each split into multiple orthogonal codes, for example Walsh codes. The communication system additionally comprising a scheduling device (31) for allocating for successive sets of timeslots common overhead channels, including a common pilot channel, which are allocated to the same sub-set of codes of each timeslot in the set. For successive sets of timeslots different data traffic is allocated to the same sub-set of codes of each timeslot in the set. This effectively generates a sector wide antenna beam carrying the common overhead channels and a plurality of narrow beams each of which carry different data traffic. Inter-beam interference is addressed by the application of Adaptive Modulation and Coding and by an inter-beam handoff scheme. The handoff scheme ensures that when an end user equipment is located in a cusp region between adjacent beams the antenna arrangement simultaneously transmits data traffic to that mobile station on at least both of the adjacent beams.

A base station includes a reference signal allocator that allocates a first layer of dedicated reference signals and a second layer of reference signals to the same resource elements in a first resource block. The reference signals are allocated to two adjacent resource elements corresponding to a first OFDM symbol and a second OFDM symbol on a first, second, and third subcarriers of the first resource block. The base station also includes a reference signal multiplexer that multiplexes the first layer with the second layer. A first cover code W1 is applied to the first layer. A second cover code W2, different from the first cover code, is applied to the second layer in a first and third subcarriers, and a variation of the second cover code W2 is applied to the second layer in a second subcarrier.

A base station is provided for receiving an acknowledgement or negative acknowledgement (ACK/NACK) signal, including a transmitting unit configured to transmit a control signal using one or a plurality of CCE(s). The base station also includes a receiving unit configured to receive an ACK/NACK signal, the ACK/NACK signal being multiplied by an orthogonal sequence, by a sequence defined by a cyclic shift, and by either a first value or a second value, wherein the first value rotates a constellation of the ACK/NACK signal by 0 degrees and the second value rotates the constellation of the ACK/NACK signal by N degrees, which is different from 0 degrees.

A base station which performs Multiple Input Multiple Output (MIMO) transmission. A processor configured to generate reference signals by spreading with four groups of orthogonal code sequences, each group of orthogonal code sequences including four orthogonal sequences, wherein the orthogonal code sequences correspond to transmission layers and each of the orthogonal code sequences has a length of four, and a transmit circuit configured to transmit the reference signals. The four groups include a first group where the orthogonal code sequences are Walsh code sequences, a second group where the orthogonal code sequences are represented by mirroring of the orthogonal code sequences in the first group, a third group where the orthogonal code sequences are represented by cyclic shifts of the orthogonal code sequences in the first group, a fourth group where the orthogonal code sequences are represented by mirroring of the orthogonal code sequences in the third group.

According to the invention, a data stream with continuous, periodic transmitted, spread data signals of N chips each is split into two data streams of N chips each, which are shifted by N chips; for each of these data streams the correlation functions are calculated within every chip clock time and, in relation to their maxima, evaluated in order to separate user signals from extraneous signals and disturbing signals.