9CDMA Spreading Principle: Multiple Successive Spreadings are Reversible
10How Many Spreading Sequences Do We Need How Many Spreading Sequences Do We Need? (Discriminating Among Forward Code Channels
11How Many Spreading Sequences Do We Need How Many Spreading Sequences Do We Need? (Discriminating Among Base Station
12How Many Spreading Sequences Do We Need How Many Spreading Sequences Do We Need? (Discriminating Among Reverse Code Channels
13CDMA Magic Spreading Tool #1: Walsh Codes Note: Example of orthogonality – The coordinates used to describe the position of a mobile station at a certain time: latitude (North or South of the Equator), longitude (East or West of Greenwich), altitude (relative to sea level), and time. A change in any of these magnitudes does not affect the other three, therefore they are “orthogonal”.
31CDMA 800 MHz Cellular Spectrum Usage OrderSide “A”Side “B”12833842242425320146641605075119548678589737630810197779691736The above table is an example of CDMA channel allocation, in chronological order, which allows maximum CDMA channel packing.Note: a) requires frequency coordination with non-cellular interferesb) requires frequency coordination with A-side carrier
34CDMA PCS 1900 MHz Spectrum Usage PCS Band A1252503754100512561507175820092251025011275493 BTAs (Basic Trading Areas) are grouped into 51 MTAs (Metropolitan Trading Area s).The following tables are examples of CDMA channel allocation, in chronological order, which allow maximum CDMA channel packing. Each table represents the “preferred” set of CDMA channels according to J-STD-008.
3512525037541005125615071758200922510250112751252503754100512561507175820092251025011275132523503375PCS Band D172527503775PCS Band E182528503875PCS Band BPCS Band CPCS Band F