Communication with Earth Station

• Downlink

The table below shows the transmission wave power characteristics for downlink.

Operation Mode	Beacon Mode	Mission Mode
Type of Transmitted Data	Telemetry Data	Mission Data
Frequency	437.200MHz	437.200MHz
Bandwidth	500Hz	16kHz
Radio Wave Model	A1A	F2D
Transmitter Output	0.1W	0.8W
Modulation Speed	1200bps	1200bps
Type of Modulation	CW	FM
Polarization	Linear Polarization	Linear Polarization

Reading Telemetry Data

• Breakdown of Telemetry Data

The content of telemetry is “WS0000C0000AS0000X0000Y0000Z0000”
The breakdown of the content is below.
①WS : Satellite Name
 It is derived from the name of our satellite, (W)SEDA-(S)AT-ZERO.
②0000 : OBC Clock Time[minutes]
 Show the time since the satellite started.
③C0000 : Li+Battery Voltage
 Charging C / No charging D + 0000 (Note 1)
④ A : Type of Telemetry Data
 There are two types, A/B
⑤S0000 : Thermistor Voltage (Note 1)
⑥X0000Y0000Z0000 : Strain Voltage (3 types of X, Y, Z, 4 digits) (Note 1)

※Note 1
 The 4-digit number is the value converted to AD at the reference voltage of 5V. Each voltage value can be calculated by substituting a 4-digit number for X in equation (1).
 V=X/4096×5 (1)
 For Example, When it is expressed as WS0243C3276AS2621X1802Y2211Z2457,
it is devided like WS/0243/C3276/A/S2621/X1802/Y2211/Z2457.
Its breakdown is below.
WS:WASEDA-SAT-ZERO
0243:243 minutes have passed since the reset.
C3276:State of carge and Li+Battry voltage is 4.0V.
S2621:Thermistor voltage is 2.2V.
X1802/Y2211/Z2457 :Strain voltage is (X、Y、Z) = (2.2, 2.7, 3.0)V.

Software

• Software

1.1 Earth Station Software


Satellite orbit simulation, Doppler shift control	Calsat32
TNC	UISS, Sound modem
CW signal recorder	audaity

• Configuration

2.1 Sound Modem
 After starting Sound Modem, click Setting > Devices to configure the settings.


From the screen below, select Output device and Input device. What you choose depends on your personal computer.

Then click Settings > Modems. Set the mode of "Modem type ch:A" to AFSK AX.25 1200bd. If there is no problem, you don't need to change other parts.

This completes the Sound Modem settings.

2.1 UISS
 After launching UISS, click Setup > View port.Enter your station's callsign, and check "UZ7HO soundmodem" in Software Modem Preference

Then, click "LAN". Check "Enable LAN Mode" and click the blue checkmark at the bottom left.