Power limit device and digital radio transmitter using the same

A power-limited, digital technique used in the field of transmitters

Inactive Publication Date: 2010-01-20
NEC CORP
View PDF10 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

In this conventional example, the power of the transmitted quadrature baseband signal is calculated, and based on the calculated power value, the power of the transmitted quadrature baseband signal is limited
Therefore, for a channel transmission, the peak value of the transmitted modulation signal is limited

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
  • Power limit device and digital radio transmitter using the same
  • Power limit device and digital radio transmitter using the same
  • Power limit device and digital radio transmitter using the same

Examples

Experimental program
Comparison scheme
Effect test

no. 1 example

[0042] figure 1 is a schematic diagram showing the structure of the transmitter of the digital radio communication system according to the first embodiment of the present invention. The transmitter includes a transmission waveform shaping filter 101, a power limiting unit 102 having a function generation section 102a and a delay calculation section 102b, a quadrature modulation unit 103, a frequency conversion unit 104, a transmission power amplification unit 105, and a transmission antenna 106.

[0043] The input transmit signal 100 is a complex baseband signal composed of an in-phase signal (commonly referred to as Ich) and a quadrature signal (commonly referred to as Qch), and is supplied to a transmit waveform shaping filter 101 . The transmit waveform shaping filter 101 performs waveform shaping on the complex baseband signal 100 , and outputs the shaped complex baseband signal 201 to the power limiting unit 102 . In the power limiting unit 102, a function generating sec...

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 power limit device includes a function generation section and a delay calculation section. The function generation section calculates a power value of an input signal and generates a function for performing a power limit based on the calculated power value. The delay calculation section delays the input signal and subjects the delay input signal to power limit calculation by using the function generated by the function generation section.

Description

technical field [0001] The present invention relates to a transmitter of a digital radio communication system, and more particularly, to a power limiting unit for limiting input to a transmission power amplifying unit and a transmitter using the power limiting unit. Background technique [0002] In a radio system, from the viewpoint of efficient use of radio wave resources, it is necessary to minimize the influence of transmitted waves on adjacent frequency bands. Especially in W-CDMA base stations and the like, it is necessary to reduce the distortion of the transmitter as much as possible, so a high degree of linearity is pursued. In a transmitter, the amplifier is most closely related to linearity. An amplifier typically has an increasingly saturated output as it gets closer to its maximum output, resulting in a non-linear region. To obtain a high degree of linearity in the amplifier, the operating point is set at a point in the linear region sufficiently far from the n...

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
Patent Type & AuthorityPatents(China)
IPC IPC(8): H04B1/04H04J13/02H03F3/24H03F1/32H03F1/02H03G3/30H03G7/06
CPCH04B2001/0416H03F1/02H03G3/3036Y02B60/50H03G7/06H04B2201/70706H04B1/707
Inventor绳田日出
OwnerNEC CORP