Unlock instant, AI-driven research and patent intelligence for your innovation.

Amplifier impedance matching

A technology of amplifiers and linear amplifiers, applied in the directions of amplifiers, amplifier input/output impedance improvement, power amplifiers, etc., can solve the problems of bulky components, difficult to design and manufacture reliably, and achieve cost and weight reduction, space reduction Effect

Inactive Publication Date: 2006-08-16
SEPURA
View PDF1 Cites 5 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the ferrite components and separate magnets required for the isolator make the assembly bulky and bulky
Additionally, isolators are relatively expensive components, not only because of the materials required, but also because they are difficult to design and manufacture reliably

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Amplifier impedance matching
  • Amplifier impedance matching
  • Amplifier impedance matching

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0038] go to figure 1 , a height schematic showing the Cartesian loop amplifier 2 , the isolator 4 and the antenna 6 can be seen. Cartesian loop amplifiers can be of any convenient design. Suitable amplifiers are fully disclosed and described in WO 00 / 10247, with specific reference to image 3 . The isolator 4 is provided between the amplifier 2 and the antenna 6 and serves to dissipate the signal reflected by the antenna 6 caused by the impedance mismatch between the isolator 4 and the antenna 2, thereby ensuring that a constant predetermined impedance is presented to the amplifier 2.

[0039] figure 2 shows that, except that no isolator is provided, the other parts are figure 1 Similar schematic. Replacing the isolator with the network part 8, image 3 and 4 This network part 8 is shown more clearly in . By omitting the isolator and its associated ferrite components and magnets, significant space, weight and cost savings can be achieved.

[0040] image 3 A schem...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

A radio frequency transmitter comprising a Cartesian loop amplifier (2), a network portion (8) and an antenna (6). The network portion (8) includes a low pass LC filter that operates to transform the effective impedance presented to the amplifier (2) by the network portion (8) and the antenna (6) such that an increase in the effective impedance of the antenna (6) results in a decrease in the effective impedance presented to the amplifier (2). The network portion (8) also includes a buffering portion that comprises a resistor inside another low pass filter stage. The resistor acts as a buffer to limit the minimum impedance that is presented to the amplifier (2).

Description

technical field [0001] This invention relates to radio transmitter amplifiers, and particularly, but not exclusively, to linear amplifiers for use in digital radio (wireless communications) applications. Background technique [0002] Linear amplifiers are often required in digital radio transmitters to provide reliable linear amplification of an input signal including at least an amplitude modulation element. In such radio transmitters, the linearity and power control of the amplifier are important in order to accurately amplify the signal. In one specific example, signals for TETRA (terrestrial relay radio) include phase and amplitude modulation. The TETRA communication device uses a linear amplifier whose linearity is ensured by using Cartesian loop feedback. This arrangement is described in more detail in WO 00 / 10247. [0003] In this amplifier configuration, it is important that the average output power of the amplifier is kept constant in order to maintain linearity....

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
IPC IPC(8): H03F1/06H03F1/32H03F1/56H03F3/191
CPCH04B1/0458H03H7/38H03F1/32H03F3/24H03F1/56H03F2200/387H03F2200/504H03F1/0205H03F3/191H03F2200/391H03F2200/451
Inventor 丹尼斯·卡林
Owner SEPURA