Ultra-low power, low-noise and small size transceiver for wearable and implantable biomedical devices and neural prosthesis

There is high demand for research into the innovation and development of miniaturized electronics devices for biomedical applications such as implantable medical devices (IMD), neural prostheses (NP), embedded neural systems, body area network (BAN) systems and wireless biosensors systems (WBS) for the monitoring, treatment and diagnostics of diseases such as retinal degenerative diseases (bionic eye), hearing loss (bionic ear), and epilepsy (neurobionics). These electronic systems must be wireless as wires penetrating through human skin increase the risk of infections as they act as conduits for viruses and bacteria and they also limit the flexibility of movement for patients. It is critical to have the smallest size possible for implanted devices to minimize required space, and to have high quality implant grades and off-chip components. Therefore, an integrated design for transceivers in single chips without any cheap components is preferable. Another advantage of minimum size and integrated transceiver design in a single chip is that it minimizes power consumption and heating. Ultra-low power transceivers are essential because implanted batteries are undesirable due to their limited lifespan and the risk of infection they pose. Also, a limited amount of power can be transferred through the wireless power link system, and in the bionic eye, most of the transferred power will be consumed for stimulation in the electrodes array. Frequency is another important factor and limitation of transceiver designs in biomedical applications. The Medical Implant Communication Service (MICS) frequency band (402-405 MHz) is a relatively low frequency and has a small channel bandwidth. Therefore, achieving an ultra-low power design of less than one milliwatt remains challenging. There is a high amount of data transmitted and received in some implantable biomedical devices like retinal prostheses (bionic eyes) so high-speed transceiver systems are required for these applications.