Carrying information to acknowledge downlink transport blocks and feedback information to the system for scheduling and link adaptation of transport block CQI and ACK/NACK Physical Channel, Uplink, SF=256 A High-Speed Dedicated Physical Control Channel, or HS-DPCCH, is the third uplink channel for WCDMA. It makes it possible for changing power relations between to the dedicated … Read more
All about Antennas. What is, How Works, How Many Types. Here I write about antenna which include what is antenna, How it works, Antenna classification, Specifications of antenna, Working Band and what is antenna gain other than this about antenna I will write next. What is Antenna Antenna is a device which converts an electric … Read more
The design of a PN offset plan for CDMA is comparable to that of a signalling channel frequency plan in analog. The consequences of poor offset planning include the following: Active Set Pilot Interference – This phenomenon would occur in the active area and involve the active search window (SRCH_WIN_A). The interfering signal would need … Read more
When we talk, we pause between syllables and words. CDMA takes advantage of these pauses in speech activity. Analog to digital conversion The voice signal is converted to a digital signal using PCM. Variable rate vocoder The vocoder (Voice Coder) is used to compress the digital signal from the Codec (Code/Decode). The vocoder, used in … Read more
There are Four channel in Forward direction in cdma. PILOT CHANNEL (1) SYNC CHANNEL (1) FORWARD TRAFFIC + PAGING CHANNELS (62) PAGING CHANNELS ( MAXIMUM 7) PILOT CHANNEL PILOT SIGNALS ARE TRANSMITTED BY EACH CELL SITE TO ASSIST MOBILE RADIO IN ACQUIRING AND TRACKING THE CELL SITE DOWNLINK SIGNAL PILOT CHANNEL IS ASSIGNED CODE CHANNEL … Read more
The polarization is a radiation feature for indicating the vector special direction of field strength of electromagnetic wave. If unspecified, the spatial direction of electric field vector usually serves as the polarization direction of electromagnetic wave. The spatial direction of electric field vector is the direction of maximum radiation by antenna. The electromagnetic wave of … Read more