Patent classifications
H04B1/0025
Spectral Stitching Method to Increase Instantaneous Bandwidth in Vector signal Generators
Embodiments are described of devices and methods for processing a signal using a plurality of vector signal generators (VSGs). A digital signal may be provided to a plurality of signal paths, each of which may process a respective frequency band of the signal, the respective frequency bands having regions of overlap. The gain and phase of each signal path may be adjusted such that continuity of phase and magnitude are preserved through the regions of overlap. The adjustment of gain and phase may be accomplished by a complex multiply with a complex calibration constant. The calibration constant may be determined for each signal path by comparing the gain and phase of one or more calibration tones generated within each region of overlap. Each signal path may comprise a VSG to convert the respective signal to an analog signal, which may be combined to obtain a composite signal.
DIGITAL-TO-ANALOG CONVERTER SYSTEM AND METHOD
An Interleaved Radio Frequency Digital-to-Analog Converter (RF DAC) suitable for use in cellular base stations and optimized to give both a wide RF tuning range and a wide RF bandwidth is disclosed. The RF DAC uses two levels of interleaving, the first providing a direct conversion path from Base Band (BB) to RF, and the second providing a variable interleaving factor through the use of summation to optimize the output bandwidth as a function of the RF center frequency. Digital Interpolation, including an arbitrary sample rate conversion filter, allows the RF DAC to operate from a wide range of possible BB sample rates and the DAC sample rate is a fixed ratio of the RF center frequency. As a result, the spurious outputs from the RF DAC are in known locations that are relatively easy to filter out, minimizing the frequency planning tasks required for a complete RF system design.
Techniques and methods for aliasing digital beamformers for reduced computational loads
A phased array receiver for use with a first received analog signal and a second received analog signal, the phased array receiver including: a first analog to digital converter to generate a first received digital signal; a second analog to digital converter to generate a second received digital signal; a first down-sampler to generate a first down-sampled digital signal; a second down-sampler to generate a second down-sampled digital signal; a first polyphase low pass filter to generate a first filtered down-sampled received digital signal; a second polyphase low pass filter to generate a second filtered down-sampled received digital signal; and a beamforming core to generate a beamformed signal, wherein the first received signal is related to the first filtered down-sampled received digital signal, and wherein the second received signal is related to the second filtered down-sampled received digital signal.
Spectral stitching method to increase instantaneous bandwidth in vector signal generators
Embodiments are described of devices and methods for processing a signal using a plurality of vector signal generators (VSGs). A digital signal may be provided to a plurality of signal paths, each of which may process a respective frequency band of the signal, the respective frequency bands having regions of overlap. The gain and phase of each signal path may be adjusted such that continuity of phase and magnitude are preserved through the regions of overlap. The adjustment of gain and phase may be accomplished by a complex multiply with a complex calibration constant. The calibration constant may be determined for each signal path by comparing the gain and phase of one or more calibration tones generated within each region of overlap. Each signal path may comprise a VSG to convert the respective signal to an analog signal, which may be combined to obtain a composite signal.
Cancellation technique for second harmonic distortion and spectral image in DACS and digital transmitters
A device includes a port and a transformer. The transformer includes a first coil that has a first node and a second node and a second coil that is coupled to the output port. The device also includes a pulse generator coupled to the first node to generate two or more pulses with a first period on the first node and a delay module that is coupled between the second node of the first coil and the pulse generator. The delay module is generates a time delay to the two or more pulses of the pulse generator before the two or more pulses are delivered to the second node. The second coil provides a signal at the port.