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An overview of radio telemetry, concentrating on low power, short‐range systems which can be operated without equipment licences. Describes transmission mechanisms, aerials and the two main types of analogue modulation: amplitude modulation [AM] and frequency modulation [FM].Outlines the developments in radio data links and modulation schemes, the benefits of networks and the various methods of encoding data. Concludes that one of the biggest problems in radio telemetry is the different regulations across Europe making it virtually impossible to design a transmitter that is acceptable in more than one country. However, in Europe the situation is slowly changing, with new common standards for defining, evaluating and testing equipment coming into effect.

Equipment, Programmes, Techniques and Projects. Pye Unicam of Cambridge have introduced a new Philips system enabling strain gauge, or similar measurements, to be made without physical electrical contact, on a shaft that is rotating at almost any speed.

Describes how radio telemetry can interface with process control systems such as supervisory control and data acquisition [SCADA] and distributed control systems [DCS] greatly increasing their power and efficiency. Outlines the basis of radio telemetry, the behaviour of electromagnetic waves, frequency and wavelengths. Uses the water industry as an example of the use of a large scale and sophisticated SCADA system to provide date collection and control links over a large area. Concludes that the versatility of radio telemetry coupled with its cost‐effectiveness means that this technology can help to expand and improve communications in an increasing number of industries.

Low‐power data acquisition techniques for process monitoring are becoming increasingly important.

The development of a sensor microsystems containing all the components of data acquisition system, such as sensors, signal‐conditioning circuits, analog‐digital converter, interface circuits and embedded microcontroller (MCU), has become the focus of attention in many biomedical applications. A review of the microsystems technology is presented in this paper, along with a discussion of the recent trends and challenges associated with its developments. A basic description of each sub‐system is also given. This includes the different front end, mixed analog‐digital, power management, and radio transmitter‐receiver circuits. These sub‐system designs are presented and discussed in a comparative study and final remarks are made. The performance of each sub‐system is assessed regarding many aspects related to the overall system performance.

Telemetry capsules have existed since the 1950s and were used to measure temperature, pH or pressure inside the gastrointestinal (GI) tract. It was hoped that these capsules would replace invasive techniques in the diagnosis of function disorders in the GI tract. However, problems such as signal loss and uncertainty of the pills position limited their use in a clinical setting. In this paper, a review of the capabilities of microelectromechanical systems (MEMS) for the fabrication of a wireless pressure sensor microsystem is presented.

The circuit requirements and methods of data transfer are examined. The available fabrication methods for MEMS sensors are also discussed and examples of wireless sensors are given. Finally, the drawbacks of using this technology are examined.

MEMS for use in wireless monitoring of pressure in the GI tract have been investigated. It has been shown that capacitive pressure sensors are particularly suitable for this purpose. Sensors fabricated for wireless continuous monitoring of pressure have been reviewed. Great progress, especially using surface micromachining, has been made in recent years. However, despite these advances, some challenges remain.

Provides a review of the capabilities of MEMS.

Looks at radio frequency design relating to the expanding field of data transmission with the arrival of purpose‐made modules, particularly at 418MHz. Describes the three main types of antennae to be considered at 418 MHz, the vertical whip, the tuned loop and the helical. Discusses the parameters that are applied to systems of speed, distance, battery constraints, size, location of equipment and limited frequency allocation. Uses the example of a low power battery operated alarm system required to provide security at a stables to show how various design problems can be overcome.

Describes the basic principles of radio remote control, dealing specifically with safety aspects, transmitters, receivers, transmitted telegrams, the Hamming code to indicate the origination of errors, and emergency stop circuits. Concludes with the specification for DTI approval in the UK and a list of typical applications for remote control systems including cranes, ship unloaders, conveyors and ventilation fans.