* Generally frequency range for nano-satellites lies in VHF band. Therefore, the antenna length will lie in range of 10 - 150 cm (varies with frequency). In vibration, higher is the mass farther from the base (source of vibration), lesser is the natural frequency of the satellite. This means that if antennae are not deployed deployable, but rather fixed the the satellite body (like in the case of Pratham), then they are more vulnerable to damage due to resonance during launch, since the fundamental frequency will approach the lower limit imposed by the launch vehicle. This imposes the requirement of antenna deployment so as to keep mass closer to the base (source).