A transmitting antenna with a gain of 3 dB means that the power received far from the antenna will be 3 dB higher twice as much than what would be received from a lossless isotropic antenna with the same input power. Similarly, a receive antenna with a gain of 3 dB in a particular direction would receive 3 dB more power than a lossless isotropic antenna. Antenna Gain is sometimes discussed as a function of angle.
In this case, we are essentially plotting the radiation pattern , where the units or magnitude of the pattern are measured in antenna gain. An example of the radiation pattern plotted in terms of gain is shown in Figure Figure 1. Example Gain Pattern for an Antenna. However, more often a single number is quoted the gain is the 'peak gain' over all directions.
Antenna Gain G can be related to directivity D and antenna efficiency by: [Equation 1] The gain of a real antenna can be as high as dB for very large dish antennas although this is rare. Directivity can be as low as 1. However, the peak gain of an antenna can be arbitrarily low because of losses or low efficiency. Electrically small antennas small relative to the wavelength of the frequency that the antenna operates at can be very inefficient, with antenna gains lower than dB even without accounting for impedance mismatch loss.
Is a High Gain Antenna Advantageous? Often manufacturers of antennas be they wifi antennas, gps antennas, or tv antennas specify the antenna gain. Various signals can be applied to these systems. A special class of signals if applied as input to such a system will have it's shape retained at the output, i.
But other than that there is no difference between input and output signals. Such an input signal is an eigen function to the system and the amount by which it's amplitude changes is the eigen value of the system for that eigen function.
For LTI systems a complex exponential signal is a typical signal which retains it's shape at the output i. The 'transfer function' basically gives you an idea how the amplitude and phase may change for a particular exponential.
H s is complex function of s, so H s is its magnitude and arg H s is argument. You can say that the 'gain' of the system is H s. Similarly, consumers who make choices to become more efficient, such as choosing energy-efficient appliances or investments that have the best possible returns while serving their investment needs, end up saving money and making more in the long run.
If you need proof, just use the formula noted above and use it as a guideline to help you make some important decisions about your financial health. Accounting Tools. Accessed Oct. Your Privacy Rights. To change or withdraw your consent choices for Investopedia. At any time, you can update your settings through the "EU Privacy" link at the bottom of any page. These choices will be signaled globally to our partners and will not affect browsing data.
We and our partners process data to: Actively scan device characteristics for identification. I Accept Show Purposes. Your Money. Personal Finance. Your Practice. Popular Courses. Economics Microeconomics. Table of Contents Expand. What Is Efficiency? Understanding Efficiency. Types of Efficiency. A Historical Look. The Impacts of Efficiency. Example of Efficiency.
How Do You Calculate Efficiency? What Is Allocative Efficiency? What Is Peak Efficiency? What Is Energy Efficiency? Efficiency in an Investment. The Bottom Line. Key Takeaways Efficiency occurs when you reduce waste to produce a given number of goods or services. You can measure efficiency by dividing total output by total input. There are a number of different types of efficiency, including economic efficiency, market efficiency, and operational efficiency.
You can measure the efficiency of your investments using the return on investment figure. You can also express efficiency as a percentage by multiplying the ratio by What Is a Measure of Efficiency in an Investment? Article Sources. Investopedia requires writers to use primary sources to support their work. These include white papers, government data, original reporting, and interviews with industry experts.
We also reference original research from other reputable publishers where appropriate. You can learn more about the standards we follow in producing accurate, unbiased content in our editorial policy.
Compare Accounts. The offers that appear in this table are from partnerships from which Investopedia receives compensation. This compensation may impact how and where listings appear. Investopedia does not include all offers available in the marketplace. Related Terms Operational Efficiency Definition Operational efficiency is a metric that measures the efficiency of profit earned as a function of operational costs.
Economic Efficiency Definition Economic efficiency is an economic state in which every resource is optimally allocated to serve each person in the best way while minimizing waste.
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