Method for improving output frequency precision of mobile phone, device and mobile phone thereof

A technology for output frequency and mobile phone, which is applied in the transmission system, telephone structure, telephone communication, etc. It can solve the problems of output frequency accuracy floating, unsatisfactory, and limitation of mobile phone output frequency accuracy, so as to improve output frequency accuracy and output frequency accuracy The effect of high and large range of control

Active Publication Date: 2013-01-09
SPREADTRUM COMM (SHANGHAI) CO LTD
View PDF0 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Therefore, the result of the compromise between the two factors is that the crystal frequency accuracy cannot be particularly high, which limits the output frequency accuracy of current mobile phones.
For example, 13bit AFC causes the change of load capacitance to be 3pF, and a crystal (DCXO) with a frequency pull of 20ppm / pF is selected, then the control range of AFC is 60ppm, and the output frequency accuracy is 60×902.4 / 2 13 =6.6Hz / bit, where 902.4Hz is the output frequency of the middle channel of the GSM band of the mobile phone; if a crystal (DCXO) with a frequency pulling degree of 10ppm / pF is selected, the output frequency accuracy is 60×902.4 / 2 13 =3.3Hz / bit, but the control range of AFC is only 30ppm, which cannot meet the demand
[0005] In addition, during mass production, due to the difference between crystals, the consistency of the output frequency accuracy is not good, and the output frequency accuracy may have a large fluctuation

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
  • Method for improving output frequency precision of mobile phone, device and mobile phone thereof
  • Method for improving output frequency precision of mobile phone, device and mobile phone thereof
  • Method for improving output frequency precision of mobile phone, device and mobile phone thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0021] Please refer to figure 1 As shown, in the mobile phone 100 of an embodiment of the present invention, the crystal 101 is connected to the crystal oscillator circuit 102 to output a reference frequency F ref , the crystal oscillating circuit 102 also has components (not shown) that can be adjusted to change the reference frequency, such as variable capacitors, but the present invention is not limited thereto. Reference frequency F ref is output to the phase-locked loop 103 for frequency multiplication to generate an output frequency F o , and then provided to the transmitting module 105 and the receiving module 106 for use, with the output frequency F o The signal as the carrier wave is transmitted by the radio frequency front-end module 107 of the mobile phone through the antenna 108 of the mobile phone. In the illustrated embodiment, the crystal oscillating circuit 102 , the phase-locked loop 103 , the transmitting module 105 and the receiving module 106 are, for ex...

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

The invention discloses a method for improving output frequency precision of a mobile phone, a device and a mobile phone thereof. A phase-locked ring of fractional frequency-division structure is used as a first accurate precision to adjust the output frequency of the mobile phone; subsequently, an automatic frequency control (AFC) signal is used as a second precision less accurate than the firstprecision to adjust the output frequency of the mobile phone. Therefore, the output frequency precision of the mobile phone is improved and the control range requirement of the crystal can be met.

Description

technical field [0001] The invention relates to the control of mobile phone frequency, in particular to a method and device for improving the output frequency accuracy of the mobile phone, and a mobile phone with the device. Background technique [0002] The initial transmitting and receiving frequency of the mobile phone is closely related to the parameters of the crystal on the mobile phone, so the initial parameters of each crystal of the mobile phone need to be calibrated. The calibration of the initial parameters of the crystal is realized by changing its load capacitance. The change of load capacitance can be indirectly reflected by the output frequency of the mobile phone in the test mode. The precise adjustment of the load capacitance can be realized by adjusting the variable capacitance (varactor diode) in the RF transceiver oscillator circuit by the automatic frequency control (AFC) signal directly or indirectly controlled by the baseband chip. [0003] There are...

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 & Authority Patents(China)
IPC IPC(8): H04B1/40H04M1/725H04M1/02H04M1/72448
Inventor 黄文韬赵国涛刘入忠施武林
Owner SPREADTRUM COMM (SHANGHAI) CO LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap