Dong Zhang

US Patent:

20020127939, Sep 12, 2002

Filed:

Oct 31, 2001

Appl. No.:

10/000671

Inventors:

Charles Hwo - Sugar Land TX, US
Houston Brown - Houston TX, US
Dong Zhang - Knoxville TN, US
Christine Sun - Knoxville TN, US

International Classification:

D04H001/00
D04H003/00
D04H005/00
D04H013/00

US Classification:

442/347000, 442/327000, 442/340000, 442/362000, 428/374000

Abstract:

This invention is a bicomponent meltblown microfiber nonwoven material wherein at least two different polymers have been extruded and spun together in either a side by side or core/sheath configuration and wherein at least one of the polymers is polytrimethylene terephthalate (PTT) and at least one of the polymers is one of but not limited to the following thermoplastics: polypropylene (PP), polyethylene (PE), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyamide (PA), and polylactide (PLA). The ratio of PTT to the other component ranges from 1:99 to 99:1, based on the weight of the polymers. The preferred weight ratio range of PTT:PP is 25:75 to 75:25 and the most preferred range is 25:75 to 50:50. The present invention also provides a process for making such a bicomponent fiber. The present invention also provides a process for making such a meltblown microfiber nonwoven material.

US Patent:

20030124941, Jul 3, 2003

Filed:

Nov 1, 2002

Appl. No.:

10/285832

Inventors:

Charles Hwo - Sugar Land TX, US
Dong Zhang - Knoxville TN, US
Christine Sun - Knoxville TN, US
Ian Carson - Dion-le-Val, BE

International Classification:

D04H001/00
D04H003/00
D04H005/00

US Classification:

442/401000, 442/361000, 442/364000, 442/362000

Abstract:

This invention is a spunbonded nonwoven material which is formed of polytrimethylene terephthalate (PTT). This material may be a microfiber material which is 1 dpf or less in fiber diameter. This nonwoven material is unique in that it has a hydrostatic head of no more than 10 cm, preferably no more than 5 cm.

US Patent:

20150042412, Feb 12, 2015

Filed:

Aug 7, 2013

Appl. No.:

13/961861

Inventors:

- San Diego CA, US
Yanjie Sun - Boxborough MA, US
Zhenying Luo - Boxborough MA, US
Zhenqi Chen - Acton MA, US
Calogero D. Presti - San Diego CA, US
Xinwei Wang - Dunstable MA, US
Dong Zhang - Boxborough MA, US

Assignee:

QUALCOMM Incorporated - San Diego CA

International Classification:

H03H 7/48
H01P 5/18

US Classification:

333112

Abstract:

Techniques for efficiently integrating directional coupler circuitry with other circuit elements of an RF front end. In an aspect, one or more inductors of an RF front end filter is incorporated into a first inductor of the directional coupler, and a capacitor is further coupled in parallel with the first inductor. In another aspect, circuitry associated with matching components of the RF front end may further be incorporated into the directional coupler design. Further techniques are provided for coupling directivity tuning elements to a second inductor of the directional coupler to improve the linearity of the coupler over other tuning techniques.