[updated: March 2017]
NEXUS (Next Education ✕ Unique Satellite) is a 1U CubeSat developed by The Japan MASAT Association (JAMSAT) and our laboratory. NEXUS was launched by JAXS's Epsilon Rocket#4 from Uchinoura Space Center in 18th January 2019.
JAMSAT developed the linear transponder and high speed transmitter, and our laboratory developed the bus system. You can see the detail of NEXUS at the web site of NEXUS.
The bus system of NEXUS is based on the heritage of the technology used in SEEDS and SPROUT, but improved so as to fix the problems occured in SPROUT bus system. The mission of NEXUS is as follows:
- Demonstration of π/4 shift QPSK transmitter
- We will realize 38400bps downlink which is relatively faster than the downlink speed of conventional amateur CubeSats.
- Demonstration of FSK transmitter
- We will demonstrate the small FSK transmitter with variable transmitteing speed.
- Verification of practicability of π/4 shift QPSK transmitter
- We will operate NEXUS using the π/4 shift QPSK transmitter, show it is practically useful with enough net speed compared with the conventional transmitters, and provide it to the CubeSat community.
- Verification of practicability of FSK transmitter
- We will operate NEXUS using the FSK transmitter, show its practicability, and provide more stable and effective FSK transmitter to the CubeSat community.
- Operation of linear transponder
- We will operate the transponder which is desired by many amateur radio people (especially in Japan).
- Demonstration of small, multi-functional, and versatile camera system
- Combined with high speed transmitter, we will provide the subsystem that can downlink the photos with higher resolution than conventional ones.
- Development of the map of elactric field strength around 500km altitude
- We will develope the map of elactric field strength around 500km altitude using the linear transponder.
The right figure illustrates the sequence of the operation of NEXUS. The operation of NEXUS is going very well so far. The mission 1, 2, and 5 has been completed until 26th January, 2019.