Abstract: A wireless data transmission apparatus is disclosed, comprising one or more antennas for transmitting data as polarised electromagnetic radiation, and polarisation control means for controlling an axial ratio and a tilt angle of the polarised electromagnetic radiation such that the axial ratio and tilt angle conveys information about the data being transmitted. A corresponding wireless data receiving apparatus is also disclosed. In some embodiments, the one or more antennas comprises a patch antenna, and the polarisation means may comprise a mechanism for varying an electrical length of the angled slot. By utilising the tilt angle and axial ratio of polarised electromagnetic radiation to convey information to the receiver, the spectral efficiency of the system can be increased. A further increase in spectral efficiency may be obtained by using the polarisation control means to modulate first and second carrier waves, and transmitting different data on the first and second carrier waves.

Abstract: In accordance with embodiments, methods for data communications are disclosed. A device obtains a forward error correction (FEC) encoded bit stream. The device maps the FEC encoded bit stream to produce a set of symbols according to a bit-to-symbol mapping rule. The bit-to-symbol mapping rule comprises a first mapper bit position associated with a first mapper error protection level and a second mapper bit position associated with a second mapper error protection level. The first mapper error protection level is greater than the second mapper error protection level. The device then transmits the set of symbols in the communications system.

Abstract: A wireless data transmission apparatus is disclosed, comprising one or more antennas for transmitting data as polarised electromagnetic radiation, and polarisation control means for controlling an axial ratio and a tilt angle of the polarised electromagnetic radiation such that the axial ratio and tilt angle conveys information about the data being transmitted. A corresponding wireless data receiving apparatus is also disclosed. In some embodiments, the one or more antennas comprises a patch antenna, and the polarisation means may comprise a mechanism for varying an electrical length of the angled slot. By utilising the tilt angle and axial ratio of polarised electromagnetic radiation to convey information to the receiver, the spectral efficiency of the system can be increased. A further increase in spectral efficiency may be obtained by using the polarisation control means to modulate first and second carrier waves, and transmitting different data on the first and second carrier waves.

Abstract: In accordance with embodiments, methods for data communications are disclosed. A device obtains a forward error correction (FEC) encoded bit stream. The device maps the FEC encoded bit stream to produce a set of symbols according to a bit-to-symbol mapping rule. The bit-to-symbol mapping rule comprises a first mapper bit position associated with a first mapper error protection level and a second mapper bit position associated with a second mapper error protection level. The first mapper error protection level is greater than the second mapper error protection level. The device then transmits the set of symbols in the communications system.

Abstract: A method of forming metal traces is disclosed, including: forming a bottom anti-reflection coating (BARC) layer and a patterned photoresist layer both on a metal layer; trimming the patterned photoresist layer and concurrently etching away a partial thickness of the BARC layer; and etching the metal layer with the trimmed patterned photoresist layer as a mask to form the metal traces. According to the method, the BARC layer is etched concurrently with the trimming of the patterned photoresist layer, dispensing with the need for separate opening of the BARC layer, which may exert adverse impacts on the line width of the metal traces. Therefore, metal traces with a uniform line width can be obtained with a significantly reduced risk of metal bridging and higher manufacturing yield.

Abstract: Provided are a pilot signal transmission method and apparatus, and a transmitting terminal. The method includes: setting a first pilot signal, a second pilot signal, and a third pilot signal on a same subcarrier; and transmitting the first pilot signal, the second pilot signal, and the third pilot signal respectively on three continuous symbols on the same subcarrier. The first pilot signal, the second pilot signal, and the third pilot signal are all nonzero data, a phase difference between the first pilot signal and the second pilot signal is 90 degrees, a phase difference between the third pilot signal and the second pilot signal is 90 degrees, and a phase difference between the first pilot signal and the third pilot signal is 180 degrees.

Abstract: A method of performing fast orthogonal frequency division multiplexing (FOFDM) includes: receiving a symbol transmitted in a multi-carrier communication system, wherein the symbol represents at least part of a transmitted signal, wherein the symbol is modulated based on a discrete cosine transform (DCT) technique; and estimating the symbol by using a widely linear (WL) estimation technique to minimize a difference between the received symbol and the estimated symbol.

Abstract: Provided are a pilot signal transmission method and apparatus, and a transmitting terminal. The method includes: setting a first pilot signal, a second pilot signal, and a third pilot signal on a same subcarrier; and transmitting the first pilot signal, the second pilot signal, and the third pilot signal respectively on three continuous symbols on the same subcarrier. The first pilot signal, the second pilot signal, and the third pilot signal are all nonzero data, a phase difference between the first pilot signal and the second pilot signal is 90 degrees, a phase difference between the third pilot signal and the second pilot signal is 90 degrees, and a phase difference between the first pilot signal and the third pilot signal is 180 degrees.

Abstract: A method and system for demodulating high-order Quadrature Amplitude Modulation (QAM) signals is disclosed. In one embodiment, the system includes a cyclic prefix (CP) removal unit for removing a CP from a received signal to provide a first intermediate signal, wherein the first intermediate signal comprises a plurality of bits; a fast Fourier transform (FFT) unit configured to convert the first intermediate signal into a frequency domain; a soft de-mapper configured to derive a plurality of soft bits based on log-likelihood estimates of the plurality of bits, wherein the soft de-mapper derives each soft bit by using a single linear function to approximate each soft bit; and a decoder configured to decode a signal derived from the soft de-mapper into information.

Abstract: A precoding method, a precoding apparatus, a Frequency Domain Equalization (FDE) method, and an FDE apparatus are provided in the embodiments of the present invention. The precoding method includes: performing offset modulation for a transmitting signal vector; calculating a precoding matrix according to the offset-modulated transmitting signal vector and a receiver decision signal vector, where the precoding matrix is used for performing precoding for the transmitting signal vector; and performing precoding for the transmitting signal vector according to the precoding matrix. Linear precoding is performed by using the offset-modulated signal on the transmitter, and therefore, the interference caused by multiple antennas and multipath propagation is reduced, the system BER is reduced, and the complexity of implementation is low.

Abstract: A precoding method, a precoding apparatus, a Frequency Domain Equalization (FDE) method, and an FDE apparatus are provided in the embodiments of the present invention. The precoding method includes: performing offset modulation for a transmitting signal vector; calculating a precoding matrix according to the offset-modulated transmitting signal vector and a receiver decision signal vector, where the precoding matrix is used for performing precoding for the transmitting signal vector; and performing precoding for the transmitting signal vector according to the precoding matrix. Linear precoding is performed by using the offset-modulated signal on the transmitter, and therefore, the interference caused by multiple antennas and multipath propagation is reduced, the system BER is reduced, and the complexity of implementation is low.

Abstract: A precoding method, a precoding apparatus, a Frequency Domain Equalization (FDE) method, and an FDE apparatus are provided in the embodiments of the present invention. The precoding method includes: performing offset modulation for a transmitting signal vector; calculating a precoding matrix according to the offset-modulated transmitting signal vector and a receiver decision signal vector, where the precoding matrix is used for performing precoding for the transmitting signal vector; and performing precoding for the transmitting signal vector according to the precoding matrix. Linear precoding is performed by using the offset-modulated signal on the transmitter, and therefore, the interference caused by multiple antennas and multipath propagation is reduced, the system BER is reduced, and the complexity of implementation is low.

Abstract: A precoding method, a precoding apparatus, a Frequency Domain Equalization (FDE) method, and an FDE apparatus are provided in the embodiments of the present invention. The precoding method includes: performing offset modulation for a transmitting signal vector; calculating a precoding matrix according to the offset-modulated transmitting signal vector and a receiver decision signal vector, where the precoding matrix is used for performing precoding for the transmitting signal vector; and performing precoding for the transmitting signal vector according to the precoding matrix. Linear precoding is performed by using the offset-modulated signal on the transmitter, and therefore, the interference caused by multiple antennas and multipath propagation is reduced, the system BER is reduced, and the complexity of implementation is low.