Development and Prospect of Chinese Lunar Relay Communication Satellite

Table 1

Major technical performance parameters of Queqiao relay satellite.


Item	Major parameters

Orbit	Halo orbit around EML2 with Z-amplitude of 13000 km
Platform	CAST 100 small satellite platform
Mass/kg	448.7
Size/mm³	(satellite body)

Attitude control	Three-axis stabilized zero-momentum control
	Pointing control accuracy: better than 0.06°
	Pointing stability: better than 0.005°/s

Propulsion	Hydrazine propulsion system with two 70 L tanks
	Four 20 N thrusters and twelve 5 N thrusters
	Carrying 105 kg propellant can provide more than 550 m/s Δv

Power	Output power of solar array: >780 W
	Capacity of the storage battery: >45 ah

TT&C	USB + VLBI
	Date rate: 1000 bits/s (uplink)/2048 bits/s (downlink)

Relay communications	Four links between Queqiao and rover/lander (X band), one link between satellite and earth (S band, X band as backup)
	A 4.2 m diameter parabolic antenna is used for communication with the rover and the lander
	A spiral antenna is used for S band data transmission
	Data rate:125 bits/s (from Queqiao to rover/lander)
	1.4/50/280/555 kbits/s (from lander to Queqiao)
	0.7/140/285 kbits/s (from rover to Queqiao)
	1/2/4/10 Mbits/s (from Queqiao to earth stations, S band or X band)

Lifetime	More than 3 years