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[培训视频]网格

离线yjantenna

UID ：127611

注册：2018-06-03
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50楼发表于: 2018-08-09 18:53:30

111111111111111111

离线evelyn

UID ：128443

注册：2018-08-03
登录：2023-02-11
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51楼发表于: 2018-08-27 15:05:23

电磁兼网格划分

离线filterdes

UID ：50438

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登录：2025-01-12
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52楼发表于: 2018-08-28 19:32:15

看看！！！！！！！！！！！！！！

新浪微博：kianjen_老师

离线lixiaoqing

UID ：63958

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53楼发表于: 2018-08-31 16:29:12

有一个系统的知识吗？光傻乎乎的用。

离线cyj佳佳

不曾见你脸上张扬过悲伤

UID ：125606

注册：2017-11-06
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54楼发表于: 2018-09-04 20:01:50

回复一下

快乐啊

离线fyunj88

UID ：16802

注册：2008-08-15
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55楼发表于: 2018-10-16 11:14:11

路过，，，，，，，，，

离线hytxiao

UID ：1049

注册：2007-02-28
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56楼发表于: 2018-11-05 10:05:37

谢谢分享，好好学习一下

离线雷蒙德

UID ：111135

注册：2013-09-22
登录：2019-03-06
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57楼发表于: 2018-11-09 10:04:48

谢谢分享，学习学习

离线gofgo

UID ：70003

注册：2010-12-01
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58楼发表于: 2018-11-09 11:50:13

666cated by the time involved in determining a “good” vs. “bad”
result. A single A-GPS fix can take over 20 seconds, and
repeated fixes are required as the power is lowered and also
to obtain a level of statistical confidence that the appropri-
ate sensitivity level has been determined. To do this from all
directions around a device could easily require days of testing.
As an alternative, a method was developed to take measure-
ments from the A-GPS device itself to help determine the
radiation pattern of the device. The resultant pattern is then
normalized to a single EIS sensitivity search to determine an
estimate for the entire EIS pattern.
The test procedure consists of five steps:
• Antenna pattern
• Linearization
• Radiated sensitivity
• TIS, UHIS, and PIGS calculation
• Intermediate channel degradation
In addition to understanding the test method for A-GPS
OTA, it is very important to understand the significance of each
measurement and how it is used to quantify the A-GPS per-
formance of devices. This in turn allows device manufacturers
to make better-performing devices and network operators to
ensure that devices launched on their network perform well.
Antenna Pattern
The first part of the A-GPS OTA Test Plan calls for measure-
ment of the GPS antenna pattern.
An antenna pattern can be represented visually to identify
the wireless device’s ability to effectively receive signals from
different directions. Imagine the antenna at the center of the
shape in Figure 5; the areas with large peaks signify the
directions from which the antenna will receive most effectively.
Figure 5. Typical GPS Antenna Pattern
Antenna pattern measurement is very important in quantify-
ing the true performance of GPS antennas in mobile devices. As
devices become smaller, lower cost and more powerful, the trade-
offs between size, cost, and performance become more difficult.
This is also true for GPS antennas which are now embedded in
nearly all high-end mobile devices and an increasing number of
mid- and low-end devices. For these devices to deliver a good
user experience for location-based applications, the GPS antenna
pattern should be compromised as little as possible.
The antenna pattern of a device can be impacted by a
number of factors including, but not limited to:
• GPS antenna design
• Device form factor
• Location of the GPS antenna in the device
• Presence of a human head or hand near the device

etermination of the TIS for an A-GPS device is compli-
cated by the time involved in determining a “good” vs. “bad”
result. A single A-GPS fix can take over 20 seconds, and
repeated fixes are required as the power is lowered and also
to obtain a level of statistical confidence that the appropri-
ate sensitivity level has been determined. To do this from all
directions around a device could easily require days of testing.
As an alternative, a method was developed to take measure-
ments from the A-GPS device itself to help determine the
radiation pattern of the device. The resultant pattern is then
normalized to a single EIS sensitivity search to determine an
estimate for the entire EIS pattern.
The test procedure consists of five steps:
• Antenna pattern
• Linearization
• Radiated sensitivity
• TIS, UHIS, and PIGS calculation
• Intermediate channel degradation
In addition to understanding the test method for A-GPS
OTA, it is very important to understand the significance of each
measurement and how it is used to quantify the A-GPS per-
formance of devices. This in turn allows device manufacturers
to make better-performing devices and network operators to
ensure that devices launched on their network perform well.
Antenna Pattern
The first part of the A-GPS OTA Test Plan calls for measure-
ment of the GPS antenna pattern.
An antenna pattern can be represented visually to identify
the wireless device’s ability to effectively receive signals from
different directions. Imagine the antenna at the center of the
shape in Figure 5; the areas with large peaks signify the
directions from which the antenna will receive most effectively.
Figure 5. Typical GPS Antenna Pattern
Antenna pattern measurement is very important in quantify-
ing the true performance of GPS antennas in mobile devices. As
devices become smaller, lower cost and more powerful, the trade-
offs between size, cost, and performance become more difficult.
This is also true for GPS antennas which are now embedded in
nearly all high-end mobile devices and an increasing number of
mid- and low-end devices. For these devices to deliver a good
user experience for location-based applications, the GPS antenna
pattern should be compromised as little as possible.
The antenna pattern of a device can be impacted by a
number of factors including, but not limited to:
• GPS antenna design
• Device form factor
• Location of the GPS antenna in the device
• Presence of a human head or hand near the device

离线qzposehun

UID ：127060

注册：2018-04-29
登录：2018-11-10
发帖：63
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59楼发表于: 2018-11-09 22:20:37

1111111111111111

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