Mumbai University > Electronics and telecommunication engineering> Sem 7 > mobile communication

Marks: 10M

Year: Dec 2015

• A software defined radio is one that can be configured to any radio or frequency standard through the use of software.
• The phone should automatically switch from operating on CDMA frequency to a TDMA frequency whenever it is required.
• The user can download Digital Signal Processing Software (DSPS) describing the desired elemental components with Digital Signal Processing Hardware (DSPH) of only 1 terminal.
• An SDR is a radio communication system where components that have typically been implemented in hardware such as mixers, filters, amplifiers, modulators, detectors, are instead implemented in software.

• Benefits of SDR:

  • SDR gives freedom to user to select the most appropriate air interface to be used based on channel conditions, traffic, cost.
  • SDR reduces the amount of software.
  • It reduces the amount of industrial waste.
• An SDR can provide software control of a variety of modulation techniques, wideband or narrowband operations, security mechanisms.
• Software-defined radios have significant utility for cell phone services, which must serve a wide variety of changing radio protocols in real time.

• In the ideal SDR, the antenna connects directly to the Low Noise Amplifier (LNA) and analog-to-digital converter (ADC) for the reception path, or the Power Amplifier (PA) and digital-to-analog converter (DAC) for the transmission path.

• The processor handles all radio functions, such as filtering, up/down conversion, modulation and demodulation, and the digital baseband.

• With SDR, the standards are implemented in software, to be loaded and executed in a common hardware platform consisting of FPGA and DSP chips.

Important SDR capabilities are:

1. The SDR module is capable of reconfiguring RF and can be programmed to tune to a wide spectrum range and operate on any frequency bands within the range.
2. SDRs can be quickly and easily upgraded with enhanced features.
3. SDRs can talk and listen to multiple channels simultaneously.
4. Diverse needs for different systems can now be satisfied with a single generic hardware, thus achieving great interoperability among various wireless networks.
5. The potential of SDR is maximized when combined with spectrum sensing and cognitive engine.
6. SDR has a broad spectrum of applications for both military and civilian wireless networks, many of which may require supporting a wide variety of evolving wireless protocols in real time.

Advantages for Customers:

• Unlimited global roaming.
• One terminal for many service.
• New services provided without needing to upgrade hardware.
• Bugs fixed without need to recall the product.