Abstract: Q of resonant elements formed over lossy substrates such as in a CMOS process is improved by forming the ground plane of the resonant element immediately over a high impedance layer to reduce cross coupling and eddy currents. A new type of meandering hairpin resonator configuration is also introduced providing, for example, for 4th order cross coupled filters of high selectivity and compact layout.

Abstract: A monolithic antenna element comprises a microstrip patch antenna and a ground plane, with a substrate between the patch antenna and the ground plane. A feeding via extends from the ground plane layer through the substrate to the patch antenna, connecting to the antenna distal from lateral edges of the antenna. A coplanar waveguide (CPW) feed line is formed in the ground plane layer, and interrupts and is electrically distinct from the ground plane. The CPW extends from a lateral edge of the ground layer to the feeding via. The antenna can be flip chip bonded to a CMOS die, reducing cost of millimeter wave transceivers, e.g. 57-64 GHz. The antenna is fabricated using standard PCB technology and a single substrate for the antenna. Antenna arrays can be fabricated. Appropriately designed antenna feeds, flip chip interconnects and antenna shape provide suitably broad antenna bandwidth, with relatively high efficiency.

Abstract: This invention concerns the estimation of signal to noise ratio (SNR) at a communications receiver; it may be applicable to a wide range of receivers but is particularly suited for Orthogonal Frequency Division Multiplexing (OFDM) receivers. In particular the invention is a method, a receiver and software for performing the method. The signal to noise ratio (SNR) in the received signals is estimated by directly estimating the power ratio, in the received signal, between the part of the frequency spectrum of the received signal that contains only noise, and the part of the spectrum that contains both signal and noise; and averaging this value over a time interval.

Abstract: This invention concerns a sub-harmonic homodyne mixer suitable for operation at the millimeter waveband (MMW); for instance the 60 GHz RF radio band. The mixer comprises: A first pair of transistors connected together with common source and common drain, and having an input port across their gates to receive the in-phase voltage signal from a local oscillator. A second pair of transistors also connected together with common source and common drain, and having an input port across their gates to receive the quadrature voltage signal from the local oscillator. Wherein, an input voltage port is defined directly across the common sources of the first and second pairs of transistors, and an output voltage port is defined between the common drains of the first pair of transistors and the common drains of the second pair of transistors. According to another aspect the present invention is a transceiver comprising a mixer according to the first aspect.

Abstract: This invention concerns soft-decision demapping of Quadrature Amplitude Modulation (QAM) signals to enable soft-decision channel decoding in a communications system. In a first aspect the invention is a method for performing the soft-decision demapping of Quadrature Amplitude Modulation (QAM) signals to enable soft-decision channel decoding in a communications system. The method comprises the steps of Extracting baseband signals from both I-and-Q channels. Sampling the baseband signals to extract a stream of complex numbers. Converting the stream of complex numbers to frequency domain vectors with components for each subcarrier frequency. Approximating bit log-likelihood ratios for each symbol directly from the real and imaginary parts of the corresponding frequency vector, without equalization by the estimated channel. And, soft-decoding of the channel codes using the approximated log-likelihood ratios.

Abstract: In one aspect, the method of synchronizing a communications device in a wireless communications network comprises receiving a beacon signal at a first frequency; and receiving a data signal at a second frequency, the beacon signal being used to synchronize reception of the data signal. In another aspect, the method comprises transmitting a beacon signal at a first frequency; and transmitting a data signal at a second frequency, the beacon signal being useable to synchronize reception of the data signal. The first frequency is substantially less than the second frequency such that the beacon signal experiences substantially different frequency-dependent propagation effects to the data signal.

Abstract: A Symbol vector for RF transmission after multiplexing onto a subset of a set of subcarriers using OFDM is transformed to the time domain. A first time domain cancellation vector is generated from a basis vector that has the same dimensionality as the symbol vector. In the frequency domain the basis vector has a substantially zero value in each of a first subset of sub-carriers of the symbol vector and in the time domain the difference between a first element of the basis vector having the highest value and a second element of the basis vector having the next highest value is maximized. The first cancellation vector is subtracted from the symbol vector to produce modified symbol vector having reduced Peak-to-Average Power Ratio (PAPR). A second cancellation vector is generated using the modified symbol vector and is used to produce a second modified symbol vector having reduced PAPR.