摘要:
An actively biased oscillator (200) includes a set of current sensing components (214,216) for sensing the amount of current flowing into the first terminal of the amplifier; and a differential amplifier (212) responsive to the current sensing components for automatically adjusting the amount of current flowing into the second terminal of the amplifier.
摘要:
A radio frequency variable gain amplifier (204) has a plurality of outputs. The amplifier (204) includes a transistor amplifier (330) having a plurality of switchable fixed gain states for amplifying an oscillator signal. The amplifier (204) includes a biasing circuit (302, 306, 312, and 316) for selectively biasing the transistor amplifier (330) to produce the plurality of switchable fixed gain states. The biasing circuit (302, 306, 312, and 316) includes switches (310 and 320) for switching between the switchable fixed gain states of the transistor amplifier (330).
摘要:
An electrical module assembly (100) includes a mounting frame (130) having a passage (135) extending though the mounting frame (130). A heat sink (160) is positioned within the passage (135) of the mounting frame (130). A module substrate (120) is located on or near the heat sink (160) such that there is thermal conductivity between the module substrate (120) and the heat sink (160). A heat-generating semiconductor device (122), such as a power amplifier (122), which requires heat dissipation, is positioned on the module substrate (120) such that there is thermal conductivity between the heat-generating semiconductor device and the heat sink (160). Electrical connection to the module substrate (120) is provided through the mounting frame (130).
摘要:
A frequency synthesizer circuit, having first and second modes of operation, comprises a voltage-controlled oscillator (VCO) (64), a low-pass filter (74), a phase-locked loop (PLL) (67), an analog-to-digital converter (50), a digital-to-analog converter (56), a controller (48), and a VCO input switch. During the first mode, the VCO input switch couples the control input of the VCO to a control signal produced by the PLL, and the analog-to-digital converter measures the control signal and provides it to the controller which stores the control voltage measured by the analog-to-digital converter. During the second mode, the VCO input switch couples the control input of the VCO to the digital-to-analog converter which applies the stored control to the control input of the VCO.
摘要:
A surface mountable molded electronic component (100) is made from formed wire having a main portion (202) and end portions (102 and 104) connected to the main portion (202). The electronic component (100) includes a first and second recess areas (108 and 110) in molded section (114) for allowing the end portions (102 and 104) to lie inside and provide for the component (100) to be surfaced mounted onto a printed circuit board.
摘要:
A stripline split-ring resonator bandpass filter comprises first and second conducting layers and first and second substrates connected to each other between the conducting layers. A first stripline ring resonator is located on the top side of the second nonconducting substrate and is coupled to the input port of the BPF. The first stripline ring resonator has a gap located therein. A second stripline ring resonator is also located on the top side of the second nonconducting substrate between the first stripline ring resonator and the output port of the BPF. The second stripline ring resonator has a gap located therein. The first substrate has at least two slots therein to allow lumped capacitors to be placed in the gaps in the first and second ring resonators.
摘要:
A null-pilot symbol assisted fast automatic frequency control (AFC) system for coherent demodulation of carrier phase modulation (CPM) includes (209) a pilot clock driven phase differentiator (252,253,255) for operating once every pilot clock cycle to determine the difference between the phase at a current pilot symbol location and the phase at a previous pilot symbol location. A frequency offset selector (256) is then used for choosing the most likely frequency offset from amongst a set of all frequency offsets that give rise to the same phase difference.
摘要:
A shielded microstrip assembly (100)includes a substrate 102 having a first ground plane surface (106) and a second surface (206) which includes a transmission line (216). A plurality of solder balls (104) provide electrical interconnection for the ground plane and for the terminals (210) and (212) of transmission line (216). The microstrip assembly (100) is then inverted and attached using solder balls (104) to a carrier (302). The inverted microstrip assembly (100) of the present invention provides for improved shielding, while maintaining the high Q and other advantages associated with a microstrip.
摘要:
An integrated-distributed-resistive-capacitive network (100) having a high dielectric electronically-tunable semiconductor integrated capacitor. The network (100) also includes a resistive layer (126) formed on the high dielectric semiconductor integrated capacitor, to provide the distributed resistance of the network (100). External contact to the resistive portion of the network (100) is provided via a plurality of contact terminals (122A and 122B) which are coupled to the resistive layer (126).
摘要:
An inductor structure, that houses a shorted transmission line inductor, includes components mounted within the volume carrying the shorted transmission line. Dielectric substrate layers which carry the shorted transmission line components and the electronic devices when sandwiched together can be coated with a metallic layer that acts as a shield protecting the internal components from external undesired sources. Mounting components within the inductor volume potentially saves space on a circuit board.