The document discusses different methods for establishing channels in radio technologies: FDMA uses different frequencies for each user; TDMA uses different time slots on the same frequency; W-CDMA uses unique code patterns to distinguish each user on the same frequency. It also describes the UMTS frame format and power control mechanisms in UMTS, including inner loop power control which adjusts transmission power based on comparisons to Eb/Nt objectives, and outer loop power control which estimates Eb/Nt objectives based on measured frame error rates.

3. • The transmission medium is a resource that can be subdivided into
individual
• channels according to different criteria that depend on the
technology used.
• Here’s how the three most popular radio technologies establish
channels:
• • FDMA (Frequency Division Multiple Access)
• - Each user is on a different frequency
• - A channel is a frequency.
• • TDMA (Time Division Multiple Access)
• - Each user is on a different window in time (“time slot”)
• - A channel is a specific time-slot on a specific frequency.
• • W-CDMA (Wide-band Code Division Multiple Access)
• - Each user uses the same frequency all the time, but it is mixed
with different
• distinguishing code patterns. A channel is a unique (set of) code
pattern(s).

6. • The possibility to operate in either FDD or TDD mode is allowed for efficient utilization
• of the available spectrum according to the frequency allocation in different regions.
• FDD and TDD are defined as follows:
• • FDD
• A duplex method whereby the uplink and downlink transmissions use 2 separate
• frequency bands:
• - Uplink: 1920 MHz - 1980 MHz
• - Downlink: 2110 MHz - 2170 MHz
• Each carrier is 5 MHz wide and the uplink channel is 190 MHz away from the
• downlink. So there are up to 12 pairs of carriers.
• • TDD
• A duplex method whereby the uplink and downlink transmissions are carried over
• same frequency using synchronized time intervals. The carrier still uses a 5 MHz
• band.
• FDD mode is the preferred mode for macro-cellular applications.
• TDD mode is the preferred mode for the unpaired part of the spectrum. Because
• each time-slot can be assigned a different direction, the TDD mode offers a great
• flexibility to manage duplex and asymmetric traffic. The TDD spectrum will be used
• for low mobility coverage in urban areas.

17. UMTS FRAME
• The UTRA/FDD Transmission is a continuous transmission.
The Spreading factor has
• to be chosen so that the transmission is compliant with the
UMTS Frame Format.
• A slot is equal to 2560 chips. The number of bits per slot is
variable and depends on
• the Spreading Factor.
• A Radio Frame is equal to 15 slots, or 38.400 chips, during
10 ms. It corresponds to a
• processing time element.
• The System Frame Number is a counter used for a time
reference in one cell. SFN value is given in the BCH (from 0
to 4095 frames).

21. Inner loop pc outer loop pc
• Located in BTS & UE.
• Controls power of dedicated physical channels.
• Inner loop power control
• • The base station compares the measured Eb/Nt with the
• corresponding objective and the mobile station will be ordered to
• decrease the transmission power if the measured Eb/Nt exceeds the
• objective. Otherwise, the mobile station will be ordered to increase
• the transmission power. The adjustment frequency is 1500HZ.
• Outer loop power control
• • Estimate Eb/Nt objective based on the measured Frame Error
• Rate(FER)
• Eb/Nt=bit energy/density of interference power spectrum, similar to
signal-to-noise ratio.