摘要:
Devices (1) for exchanging ultra wide band signals comprise frequency translating stages (20,30) for frequency translating signals and oscillating stages (40) for supplying main inphase/quadrature oscillation signals to the frequency translating stages (20,30). By providing the oscillating stages (40) with polyphase filters (43,44) for reducing harmonics in oscillation signals, the main oscillation signals will be sufficiently clean. The oscillating stages (40) comprise mixers (46) for converting first inphase/quadrature oscillation signals and second inphase/quadrature oscillation signals into the main oscillation signals. The polyphase filters (43,44) may be located before and after the mixers (46). Frequency selectors (45) replace prior art multiplexers located after the mixers (46). Such frequency selectors (45) comprise multiplexers (126,127) for supplying the second inphase/quadrature oscillation signals, with a combination of these second oscillation signals corresponding with a positive frequency, a negative frequency or a zero frequency, and comprise coders (125) for controlling the multiplexers (126,127).
摘要:
An oscillation signal with a selectable frequency is generated with a phase locked loop (10, 12, 14). The oscillator (10) of the loop receives a feedback signal, to which an offset is added in order to reduce transient effects when a frequency modification is made. A first and second offset control value are used to control the offset successively. The first offset control value is controlled by a combination of the frequency settings before and after the modification. The second offset control value is controlled by the frequency settings after the modification. The first and second offset control values are used to control an offset of applying to a frequency control signal of an oscillator (10) of the phase locked loop (10, 12, 14). The offset controlled by the first control offset value is applied during a predetermined time interval before the offset controlled by the second control offset value is applied.
摘要:
A frequency hopping receiver circuit has a frequency converter (12) and a hopping control circuit (14) coupled to the frequency converter (12), and configured to control frequency hopping of the received frequency, by controlling changes in frequency shift applied by the frequency converter (12). The frequency change is applied in combination with a temporary reduction in conversion gain of the frequency converter (12) during the change in frequency shift. The frequency converter may contain a mixer (122), a local oscillator circuit (120) and a controllable amplifier (124) coupled between the input of the frequency converter (12) and the mixer (122) or between the mixer (122) and the output of the frequency converter (12), or between the local oscillator circuit (120) and the local oscillator input of the mixer (122). In this case the hopping control circuit (14) has outputs coupled to a gain control input of the controllable amplifier (124) and a frequency control input of the local oscillator circuit (120), to control the reduction in conversion gain and the change in frequency shift respectively.
摘要:
A frequency hopping receiver circuit has a frequency converter (12) and a hopping control circuit (14) coupled to the frequency converter (12), and configured to control frequency hopping of the received frequency, by controlling changes in frequency shift applied by the frequency converter (12). The frequency change is applied in combination with a temporary reduction in conversion gain of the frequency converter (12) during the change in frequency shift. The frequency converter may contain a mixer (122), a local oscillator circuit (120) and a controllable amplifier (124) coupled between the input of the frequency converter (12) and the mixer (122) or between the mixer (122) and the output of the frequency converter (12), or between the local oscillator circuit (120) and the local oscillator input of the mixer (122). In this case the hopping control circuit (14) has outputs coupled to a gain control input of the controllable amplifier (124) and a frequency control input of the local oscillator circuit (120), to control the reduction in conversion gain and the change in frequency shift respectively.
摘要:
The present invention proposes a control loop for receiving a reference signal r(t) and generating an output signal c(t) based on the reference signal r(t). The control loop comprises a subtracting element(320), a correcting element(330,350), a control path(340) and a storage element(360). The subtracting element(320) generates a difference signal d(t) including a difference between the reference signal r(t) and the output signal c(t). The correcting element (330,350) generates an adjusting signal b(t) based on the difference signal d(t). The control path(340) generates the output signal c(t) based on the adjusting signal b(t). And the storage element (360) stores at least one internal state of at least the correcting element(330,350) and applies the stored internal state to at least the correcting element(330,350) based on an instruction signal i(t).
摘要:
Data is received with a transceiver circuit with a receiver branch (14) that comprises a notch filter (140) and a digital Fourier transformer (146). Furthermore the transceiver circuit has a transmitter branch (16) comprising an inverse digital Fourier transformer (160). Prior to reception the transceiver circuit is switched to a calibration mode, wherein an output of the transmitter branch (16) is coupled to an input of the notch filter (140). The inverse digital Fourier transformer (160) of the transmitter is used to compute an inverse transform of a spectrum with a frequency component at a selected position. A signal derived from the inverse transform is applied to an input of the notch filter (140) in the calibration mode. The digital Fourier transformer (146) is used to Fourier transform an output signal of the notch filter (140). A control setting of the notch filter to suppress the frequency component from an output of the digital Fourier transformer (146) is determined. A parameter derived from said control setting is stored in a memory (149a). After the transceiver circuit is switched to a reception mode, a received interfering signal and an interference frequency of the received interfering signal are detected. The stored parameter to translate the detected interference frequency into a control setting of the notch filter (140).
摘要:
The invention relates to an antenna diversity comprising a first and a second antenna element one of which is operated in an active mode whereas the other one of which is operated in a parasitic mode. It is the object of the present invention to further minimize the amount of mismatch by still being able to maximize a predetermined signal quality criterion for the electromagnetic signal on the active path between the active antenna and the transceiver. This object is solved by a switching unit 120 for either operating the first antenna element in the parasitic mode and simultaneously operating the second antenna element in the active mode or vice versa and by providing a pre-selection unit 130 as well as a selection unit 140 for selecting an optimal configuration for the antenna diversity ensuring that the amount of said mismatch is below a predetermined threshold value and that simultaneously a predetermined quality criterion for the transceived electromagnetic signal is fulfilled best. The antenna diversity further comprises a control unit 150 for adjusting said selected configuration. The invention further relates to a method for operating such an antenna diversity.
摘要:
Data is received with a transceiver circuit with a receiver branch (14) that comprises a notch filter (140) and a digital Fourier transformer (146). Furthermore the transceiver circuit has a transmitter branch (16) comprising an inverse digital Fourier transformer (160). Prior to reception the transceiver circuit is switched to a calibration mode, wherein an output of the transmitter branch (16) is coupled to an input of the notch filter (140). The inverse digital Fourier transformer (160) of the transmitter is used to compute an inverse transform of a spectrum with a frequency component at a selected position. A signal derived from the inverse transform is applied to an input of the notch filter (140) in the calibration mode. The digital Fourier transformer (146) is used to Fourier transform an output signal of the notch filter (140). A control setting of the notch filter to suppress the frequency component from an output of the digital Fourier transformer (146) is determined. A parameter derived from said control setting is stored in a memory (149a). After the transceiver circuit is switched to a reception mode, a received interfering signal and an interference frequency of the received interfering signal are detected. The stored parameter to translate the detected interference frequency into a control setting of the notch filter (140).
摘要:
A traveling-wave amplifier includes amplifiers coupled anti-parallel to transmission lines. Phase(s) of the amplifiers provide phase matching, which may additionally or alternately be provided by couplers or spatial offset of the amplifiers and couplers. The traveling-wave amplifier provides compensation for the losses of the transmission lines, amplification of the signals and isolation between input and output by coupling the amplifiers to the transmission lines anti-parallel.
摘要:
The invention relates to an antenna diversity comprising a first and a second antenna element one of which is operated in an active mode whereas the other one of which is operated in a parasitic mode. It is the object of the present invention to further minimize the amount of mismatch by still being able to maximize a predetermined signal quality criterion for the electromagnetic signal on the active path between the active antenna and the transceiver. This object is solved by a switching unit 120 for either operating the first antenna element in the parasitic mode and simultaneously operating the second antenna element in the active mode or vice versa and by providing a pre-selection unit 130 as well as a selection unit 140 for selecting an optimal configuration for the antenna diversity ensuring that the amount of said mismatch is below a predetermined threshold value and that simultaneously a predetermined quality criterion for the transceived electromagnetic signal is fulfilled best. The antenna diversity further comprises a control unit 150 for adjusting said selected configuration. The invention further relates to a method for operating such an antenna diversity.