RXM-GPS-F4-T Linx Technologies, RXM-GPS-F4-T Datasheet - Page 44

• Manufacturer Part Number: RXM-GPS-F4-T
• Description: GPS Modules F4 Series GPS Recvr Module Tape and Reel
• Manufacturer: Linx Technologies

Specifications of RXM-GPS-F4-T

• Rohs: yes
• Frequency Band: 1575.42 MHz
• Number Of Channels: 48
• Time To First Fix (cold Start): 32 s
• Acquisition Sensitivity: - 159.5 dBm
• Horizontal Position Accuracy: 3 m
• Operating Supply Voltage: 1.8 V
• Operating Supply Current: 56 mA
• Interface Type: Serial
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Dimensions: 15 mm x 13 mm x 2.2 mm
• Minimum Operating Temperature: - 30 C

Microstrip Details
A transmission line is a medium whereby RF energy is transferred from one
place to another with minimal loss. This is a critical factor, especially in
high-frequency products like Linx RF modules, because the trace leading
to the module’s antenna can effectively contribute to the length of the
antenna, changing its resonant bandwidth. In order to minimize loss and
detuning, some form of transmission line between the antenna and the
module should be used, unless the antenna can be placed very close
(<
cable; another is the microstrip. This term refers to a PCB trace running
over a ground plane that is designed to serve as a transmission line
between the module and the antenna. The width is based on the desired
characteristic impedance of the line, the thickness of the PCB, and the
dielectric constant of the board material. For standard 0.062" thick FR-4
board material, the trace width would be 111 mils. The correct trace width
can be calculated for other widths and materials using the information
below. Handy software for calculating microstrip lines is also available on
the Linx website, www.linxtechnologies.com.
Figure 52: Example Microstrip Calculations
1
Example Microstrip Calculations
Dielectric Constant
⁄
8
in) to the module. One common form of transmission line is a coax
4.80
4.00
2.55
Figure 51: Microstrip Formulas
Width/Height
Ratio (W/d)
1.8
2.0
3.0
–
40
Effective Dielectric
–
Constant
3.59
3.07
2.12
Trace
Ground plane
Impedance ()
Characteristic
Board
50.0
51.0
48.0