Table of Contents
Advertisement
Hardware Integration Guide
3.2.1.
Choosing the Correct Antenna and Cabling
When matching antennas and cabling:
The antenna (and associated circuitry) should have a nominal impedance of 50Ω with a
recommended return loss of better than 10 dB across each frequency band of operation.
The system gain value affects both radiated power and regulatory (FCC, IC, etc.) test results.
3.2.2.
Designing Custom Antennas
Note that in designing custom antennas, a skilled RF engineer should do the development to ensure
that the RF performance is maintained.
Determining the Antenna's Location
3.2.3.
When deciding where to put the antennas:
Antenna location may affect RF performance. Although the Accessory Board is shielded to
prevent interference in most applications, the placement of the antenna is still very important -
if the host device is insufficiently shielded, high levels of broadband noise or spurious
interferences can degrade the HL8548's performance.
Connecting cables between the Accessory Board and the antenna must have 50Ω
impedance. If the impedance of the Accessory Board is mismatched, RF performance is
reduced significantly.
Antenna cables should be routed, if possible, away from noise sources (switching power
supplies, LCD assemblies, etc.). If the cables are near the noise sources, the noise may be
coupled into the RF cable and into the antenna.
3.3.
RF Performances
RF performances are compliant with the ETSI recommendation GSM 05.05.
Note:
Values in the table below are preliminary and subject to change.
Table 3.
Conducted RX Sensitivity (dBm)
Frequency Band
GSM850/EGSM
DCS/PCS
UMTS B1
UMTS B2
UMTS B5/6
UMTS B8
4119996
Typical Sensitivity (dBm)
-109
-108
-110
-110
-110
-110
Rev 1.3
April 10, 2017
11
Advertisement
Table of Contents
