ZTE Corporation ZM8300G 사용자 설명서
ZTE ZM8300G Module Hardware User Manual
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Smart meter reading products such
as water meters, electricity meters,
and gas meters
Meters are installed at remote
locations,
surrounding
environments are complex, the
signal attenuation is large, and
the signal quality is poor.
1. Internal antenna
2. High-gain antenna
3. Omni-directional
antenna
4. Low cost
Car detector
Car detectors are buried in the
ground, and the signal quality is
poor.
Smart city products such as smart
streetlights and smart garbage
cans
Smart city products are installed
outdoors, so they must be easy to
install
and
require
good
waterproofing measures.
1. External antenna
2. Waterproof and
corrosion resistant
3. Low cost
Mobile products
Mobile products provide the
positioning
function.
When
mobile products move, signals
change and are unstable.
1. GPS antenna with
excellent performance
2. Omni-directional
antenna pattern, if
possible
3. Low cost
Tracker products
Tracker products are carried by
people or animals, feature small
sizes,
and
have
high
requirements for the positioning
function.
1. GPS antenna with
excellent performance
2. Considering the
impact of people or
animals on the antenna
efficiency
3. Small sizes
4. Low cost
Passive parameters used to measure the performance of an antenna include the antenna
efficiency, VSWR, return loss (S11), polarization, and radiation pattern, which are described
as follows.
4.4.2
Antenna Efficiency
The efficiency of an antenna refers to the ratio of the power radiated by the antenna to the
effective input power. The power radiated by an antenna is generally less than the input
power due to antenna loss and cable loss. The antenna loss is primarily reflected by the
antenna efficiency. Specifically, high antenna efficiency indicates low antenna loss. The
antenna efficiency is affected by the VSWR/S11 and antenna clearance area. An antenna