Satellite Navigation and Asia

Bartholomaeus Pitiscus (1561-1613) was a Polish theologian who first coined the term ‘trigonometry’ which is a branch of mathematics that deals with the relationship between the angles and sides of triangles. This aspect of geometry is of wide-ranging utility to various fields of science and technology. Trigonometry has various applications for measurement of distances. The techniques based on trigonometry are used in astronomy and for navigational systems which use the triangulation method to identify the position of an object.

Navigation is important for the armed forces for various reasons. It helps in locating ground and air targets and aids reconnaissance missions. It can be used in weapon systems like missiles and artillery and aerial platforms like manned and unmanned aircrafts. Such navigation systems have various civilian application uses too.

Navigational systems are assuming increasing importance because of its strategic applications and commercial utility. This chapter analyses the relevance of the Asian investments in navigational systems. There are certain complexities associated with navigational systems. The entire notion of navigation by using satellite means has evolved over decades. Asia is relatively a new entrant in this field. In order to evolve the context of navigation, this chapter begins with a brief overview of the history of navigation and elucidates current global investments in this field.

The basic purpose of a navigation system is the identification of location which requires a minimum of three satellites. A system is employed to calculate its position (basically in terms of distance) by measuring the distance between itself and the three satellites. The distance to each satellite is calculated by measuring the time lag between the transmission and reception of each microwave signal (which travels at a speed of light). Other information like location of the satellites is also necessary. Position identification is done by the technique of triangulation.

Essentially, navigational systems are based on two basic satellite-based positioning systems: the Global Navigation Satellite Systems (GNSS) and the Regional Navigation Satellite Systems (RNSS). Global systems normally consist

A. Lele, Asian Space Race: Rhetoric or Reality?, DOI 10.1007/978-81-322-0733-7_11, © Springer India 2013

of a constellation of satellites (minimum of 24-26 satellites) and ground stations required to control them. The RNSSs also have similar infrastructure may be lesser in quantum. These networks can be termed broadly as GNSS augmentation systems.