Antenna PCB Introduction:
At this upcoming age of 5G, the demand for antenna PCB is increasing day by day. It is now one of the biggest challenges to deliver proper and accurate antenna PCB. If we want to control any devices wirelessly then it is mandatory to have an antenna PCB. If you see the old TVs of the ’80s and ’90s then you know that you had to maintain a different angle of the big zigzag-shaped antenna to get a clear picture of different channels. The antenna is mainly a metallic structure that is able to transmit or receive electromagnetic waves. It is available in all shapes and sizes starting from little one to the biggest one which is generally used by space agencies to handle multiple devices and information between space and earth. If you are interested in wireless communication and love to work with it then you will come across designing and assembling antenna PCB. There are a lot of reasons concerning why we need or why we use an antenna, however, a significant explanation with regards to why we use an antenna is that they give a straightforward method to move guided electromagnetic waves or signals where different techniques are unthinkable.
There are different types of antennas. We use them as per our requirement:
- Short Dipole Antenna
- Dipole Antenna
- Loop Antenna
- Monopole Antenna
Log Periodic Antennas
- Bow Tie Antennas
- Log-Periodic Antennas
- Log-Periodic Dipole Array
- Slot Antenna
- Horn Antenna
- Rectangular Microstrip Patch Antenna
- Quarter-Wave Patch Antenna
- Flat-plate Reflector Antenna
- Corner Reflector Antenna
- Parabolic Reflector Antenna
- Long Wire Antenna
- Yagi–Uda Antenna
- Helical Wire Antenna
- Spiral Antenna
- Two-Element Array Antenna
- Linear Array Antenna
- Phased Array Antennas
It is one of the most commonly used antennas we have ever seen. Staring from vehicles to big ships and buildings, you can see the use of wire antennas. With different shapes and sizes such as wire, loop, and helix, it is one of the most easy-to-use antennas.
It consists of two conductors on the same axis and the length of the wire should be small compared to the wavelength.
Short Dipole Antenna:
It is one of the simplest antennas available in the market. We called it short because it uses a short wavelength. It is an open circuit antenna. The wavelength of the frequency operation must be greater than the length of the wire.
It is a special case of a dipole antenna. It has only one pole so it is called a dipole antenna.
A Loop antenna is basically made up of looping a single wire or multiple wires with multiple turns. The amount of radiation produced by a Loop antenna is almost equal to.
This type of antenna basically consists of a dipole or loop antenna.
This type of antenna has one or more slots. This type of antennas is mainly used in microwave frequencies.
Horn antenna is one of the most popular antennas. It is used widely because it has so many advantages.it affects the transition between wave propagating in free space and transmission line.
So now we have a basic idea about antennas but now we are going to discuss a few parameters which define or decide the characteristics of an antenna.
There are many parameters we are going to discuss a few of them. Such as:
- Radiation Intensity
- Radiation pattern
- Efficiency and power gain
- Input Impedance
- Effective Aperture
- Antenna Polarization
- Radiation Pattern
The radiation from an antenna cannot be the same and equal in every direction. It should be maximum in one particular direction and minimum in other directions. When the radiation graph of an antenna is just a function of direction then it is called a Radiation Pattern
If we want to calculate the radiation intensity of an antenna then we have to calculate the power per unit solid angle of that antenna. Unit of radiation intensity expressed as watts per steradian(w/sr).
Directivity and Gain:
If we think of an antenna where the amount of radiation is equal in every direction called an isotropic antenna. Although this a hypothetical condition but we are going to take it as real just to realize what is directivity and gain. The power density of an isotropic antenna is equal at every point. Then the average power of an antenna as a function of radiated power is
Pavg = Prad / 4πr2 W/m2
Now you can realize what is gained here of course it is the ratio of power density to the average power. On the other hand, Directivity can be defined as the concentration of radiation in the direction of maximum radiation.
Radiation efficiency and Power Gain: Radiation efficiency can be expressed as the ratio of radiated power to the input power.
ηr = Prad / Pin
Power gain can be expressed as the ratio of power radiated in a direction to the total power.
nput impedance is a vital parameter for antenna radiation. If the input impedance of an antenna does not match with the input transmission line then the performance of that antenna will decrease due to reflected power.
Effective length is the length of an imaginary linear antenna with a uniformly distributed current.
The range of frequencies over which the characteristics of an antenna are maintained to the specified value is called Bandwidth.
The ability of an antenna to gaining energy from the electromagnetic wave is called an effective aperture
It refers to the physical orientation of the EM wave radiated in a guided direction.
So it is now clear how the characteristics of an antenna made an impact on the performance of the whole system. Now we are going to discuss the antenna PCB and how it works, how to design an antenna PCB etc.
What is Antenna PCB:
Antenna PCB is basically a wireless device to transmit and receive signals. Almost every wireless device is using a wireless PCB.
How is Designing an Antenna PCB:
There are many types of antenna PCB. Before knowing how to design an antenna PCB we must have to know the process of choosing the right type of Antenna. The two most important steps to build any wireless device are Antenna PCB design and RF layout. There is a huge demand for compact PCB antennas operating in the ISM bands. Most of the device uses 2.4 GHz band and 915 GHz band. We are going to discuss the whole process based on the 2.4 GHz band.
There are mainly two types of antenna which are dominating other types of antenna. They are
- Inverted F antenna
- Mender line inverted F antenna
As this is a huge discussion, we are not able to cover up everything in one article so here we are going to discuss only the Mender line inverted antenna.
Antenna Calculations: Antenna Calculation is a very important step. But before calculation, we have set up some parameters correctly.
- Selecting the substrate and operating frequency
- Calculating the appropriate length and width of the substrate.
- Calculating the length and width of the trace.
Let us consider the PCB is made out of FR4 material which has a relative permeability of 4.4.
The height of the substrate can be calculated by using,
- hs = Height of the substrate,
- F= Frequency in GHz,
- C= Velocity of light in m/s,
- Σr= Substrate dielectric constant.
The Width of the trace can be determined using:
The length of the trace can be determined using:
- Σff = Effective permittivity
- Σff=(Σr+1/2) + (Σr-1/2) (1/(√1+12hs/(wₚ)))(4)
- ΔL = Physical length
Length of the Substrate is given By,
Ls = Lp + 6hs
The width of the substrate is found by,
ws = wp+ 6 hs(7)
The microstrip width to depth ratio is determined by,
- d = Width of the trace,
- w = Width of the substrate
- A = Effective area.
Now we are going to design an ESP8285 based 2.4Ghz RF board.
Designing the schematics: To design the Schematic first we have to download the hardware design guide for esp8266 from google. we have to follow that design guideline. First, we have to focus on Analog power supply & Digital Power Supply for ESP Fig 1.
2.4 GHz Antenna PCB Design:
Here SJ3 and SJ4 select between a trace antenna and UFL connector. The antenna section is created here so that we can switch it between the PCB antenna and a whip antenna. Two inductors L2 and L3 are grounded.
The Board Layout Fig 3:
So this image is the layout of the Antenna PCB board. Now you can say that there are so many things, so it is hard to figure out everything laid out on the board. Then I can suggest you just focus on the Antenna Section and the Crystal Oscillator section. Now we are going to discuss these two sections only.
Step-1.we have to place all the necessary connectors and headers.
After that, we have to place an antenna and UFL connector. Then gradually we have to place switches, for GPIO, microcontroller, and of course the programming Header.
Now we have to route the Antenna PCB. But before routing one thing we must have to remember that the trace impedance should be 50 ohms. So you have to calculate the trace impedance and you can use different online tools for this calculation such as Mantaro. We are going to show you all the calculations using Mantaro.
First, we have to put all the necessary parameters. In the above image, you can see that we put few values like Trace width 70, Trace thickness as 1.4, dielectric thickness as 39.3701, and relative dielectric constant 4.5. Now if we click on calculate we get exactly 50.509 which is almost equal to our desired 50 value.
Now as we are able to get the trace impedance as per our desired value we are now able to do the routine perfectly.
After completing the routing we get an image like this. Now the only thing we have to do is to send this design to a PCB manufacturing company to manufacture it as per our design and then we have to program it and have to test it.
That’s it. This is a short discussion about the process of how to design an Antenna PCB.
WiFi Antenna PCB Design:
We are going to design a completely easy-to-use wifi antenna PCB with an ESP8266 wifi module. Now we are going to discuss circuit diagrams. Now as we say earlier that before designing any circuit you have to read the hardware designing guideline. You can download it from google.
First, we have to design the circuit diagram for the ESP8266 Board with all possible connections and components.
Components Required for the Circuit Diagram:
- ESP8266 WiFi Module (ESP-01)
- Female Headers (a few strips)
- Push Button
- 1 KΩ Resistor (1/4 Watt)
- 2 KΩ Resistor (1/4 Watt)
- 100 nF Capacitor
- Two Way Slide Switch
As we are going to work with the ESP8266 wifi module so we have to know about the pin configuration of the ESP8266 ESP-01 variant. It has 8 pins such as
VCC,GND, TX,RX,GPIO0,GPIO2,RST(reset) and CH_PD.
VCC and CH_PD pins are connected to the VCC of the power supply header and the GND pin is connected to the GND terminal.
The RST pin is connected to a push button and the GND.
GPIO2 is connected to the female header of GPIO. on the other hand, GPIO0 is connected to the center terminal of a two-way slide switch.
The TX pin is directly connected with the TX pin of the communication female header. The RX pin is connected to the level converter consisting of a 1kohm and 2.2kohm resistor.
We are going to design the Schematic as per the circuit diagram.
The schematic is completed and you can see it is a very simple layout. So we are going to design a single-layer PCB for it.
Now we have to send this design to a PCB manufacturer for manufacturing PCB as per our design and later we will assemble all the components and then it will be ready to use.
To use it just connect the 3.3v supply to the VCC and GND pin. Now if you want to program it with your firmware then just switch to the programming mode position and press the RST button.
The final board will look like this:
What is Bluetooth Antenna PCB?
Necessary Steps to build Bluetooth antenna PCB.
Before designing Bluetooth Antenna PCB first carefully read the guidelines from the internet and build your concept about it so that you can visualize the whole thing
Bluetooth circuit is the central part of a Bluetooth and it contains components like IC, capacitors, power supply point, etc. The operating frequency of a Bluetooth connection is 2.4 GHz range. We all know that in Bluetooth operation there is at least one master device and one or many slave devices.
Bluetooth Circuit Board:
A Bluetooth circuit board must contain at least one antenna that helps to transmit and receive information. To enhance the performance of a Bluetooth circuit board we have to use at least two inductors that can fine-tune the antenna’s impedance.
Earlier we say that Bluetooth PCB operates at a range of 2.4 GHz. It is a radio frequency range that we also use in wifi technology. We know that Bluetooth communication has a master device and one or more slave devices but we have to remember that the number of slave devices we can use up to 7. Master and slave devices can work at a distance of a maximum of 10 meters. Bluetooth devices always work with exchanging some unique codes so to use Bluetooth we need approval from both the master’s end and slaves end. PCB close to the antenna can cause lower resonance frequency so it is always recommended to maintain the thickness of PCB used in Bluetooth should be 1.6mm.
Bluetooth Transmitter Circuit: Bluetooth transmitter circuit mainly deals with the transmission of data. It also helps to enable the pairing of your Bluetooth device with other devices. It contains some components including led indicators so that it can indicate when the device is connected with other devices. The main cell is protected with a small circuit so that overcurrent flow could not make any damage to the device. The Bluetooth transmitter circuit also contains voltage regulation, battery charging unit, USB module, etc.
You can supply power to the Bluetooth circuit board using two types of batteries. You can use a 1A USB supply or LiPo battery. The board is also made up of led lights and a sound facility so that it could indicate the status of connectivity.
Some of the features of the Bluetooth circuit Board is:
- It contains sound facilities and led lights to indicate the status of the connectivity all the time.
- It enables multiple devices to transfer data seamlessly using wireless connectivity
- It is designed in a simple way and programmed so smartly that users can use it without knowing much about it. The user interface of any Bluetooth device is so user-friendly.
- The Bluetooth antenna PCB is designed in such a way that it is able to connect the last paired device or to the closest device within the preferred range.
How to make Bluetooth antenna PCB:
So first we have to design the schematic. The PCB layout is one of the most challenging parts and if you are good at PCB designing then it will be perfect. We have to remember a few things when we design a Bluetooth antenna PCB.
- 1. First we need to have a Bluetooth head start, amplifier, switches, LEDs, and an enclosure. We have to ensure that the cables do not cross the head start because it can reduce the Bluetooth range.
- Try to place the system away from the transmitter because if somehow you place it near the transmitter then it could affect the normal transmission process.
- You have to choose the no of layers according to the number of features you want to add to your board. Generally, it is advised that for Bluetooth PCB you should choose multiple layered designs.
After completing the design send it to a manufacturer to manufacture it as per your design. Then assemble all the necessary components and then it will be ready to use.
What is GPS ANTENNA PCB?
Nowadays GPS is mandatory for many devices. People want to track their devices through GPS and sometimes they want to confirm the location of their lost devices. Now if you want to design a GPS Antenna PCB then you have to follow some rules and guidelines. You can go through tutorials available on the internet. We will discuss a few steps and tips to design a GPS PCB successfully.
The first step in this process is choosing the correct GPS module. There are several factors to verify before choosing a GPS module. Which module is better for you? A GPS patch antenna or GNSS antenna or ceramic patch antenna?
There are two types of GPS antenna. One is an active GPS antenna and the other one is a passive GPS antenna. The passive antenna does not have any amplifier module but active antennas have a low noise amplifier built into the module. Active antennas are set with a board and can be connected to a PCB with coax cable.
A few receivers come up pre-bundled with both types of antenna. They can likewise contain a latent coordinate with a network that coordinates with the output to 50 Ohms impedance radiation pattern. As we know that active antenna has a performance advantage because of its pre-built LNA feature or low noise amplification feature.
How does GPS Antenna PCB Design?
First you have to properly isolate or shield all the components on your board. If you are not able to shield them or cover them properly then a GPS antenna and receiver can degrade the signal. Sometimes the noise from the receiver causes so many problems when the receiver has an internal antenna. The cross-connection between the receiver and other components mainly happened due to improper shielding. On the other GPS signal has to be extracted from the LNA. We can do it by placing a SAW filter or surface acoustic wave filter in between the LNA and receiver input. The specialty of a SAW filter is that it allows for the filtering of high frequencies above 1 GHz. Such as those found in GPS applications. It is almost impossible to differentiate and filter GPS frequency from other noisy signals without a SAW filter.
Shielding, Grounding, and Routing:
Proper routing, grounding, and shielding are required in your PCB because the output signal from a GPS antenna is equal to or below 20db. So the amount of noisy signal that can be acceptable by other devices is not acceptable in a GPS antenna. At first, try to create different blocks for your main PCB. Then create separate ground for each block and at last, you can add those ground points in a star topology. We have to draw antenna traces away from the digital traces because antenna traces that go to the receiver carry digital signals. If it is possible to pass your antenna traces through a shielded enclosure then do it because it can be a safeguard for your antenna signals. There is another way to maintain a distance between antenna traces and digital traces is to pass your antenna traces through an internal PCB layer.
Design for Impedance Matching:
Attenuation and impedance matching are vital parts of high-frequency PCB design. Signals which have longer trace and higher carrier frequency can cause lower sensitivity. If you want higher sensitivity then you have to choose a shorter trace between a passive antenna and external LNA.
If you are using antenna traces that carry RF signals then it is always better to avoid Vias because it could increase the impedance of the trace. One via can add 10 ohms of impedance to trace GPS RF frequencies and can also create inductive discontinuity. In this way, you can design a GPS Antenna PCB.
After completing the PCB design we have to send the design to a PCB manufacturer who can manufacture it as per our design. Then we can assemble all the necessary components so that they will be ready to use.
What’s GSM Antenna PCB?
GSM is a Global System for Mobile Communication. As per the circuit diagram, we will create our first BOM file or bill of material file.
|1||1||C3||220nF (Ceramic Cap)|
|2||1||D1||LED (Normal Led)|
|8||4||R1,R2,R3,R9||0E (1/4W Resistance)|
As per the circuit diagram and component information we can easily construct a GSM antenna PCB. First of all a GSM module, U1 will be connected to a SIM1 or sim holder connector. Now they are connected to U2 (Voltage separation) and we can see that they are also connected to the sim holder and GSM module. There are output connectors such as JP1, JP2, JP3 and JP4.
GSM modules need a supply voltage of 5v to 20v. At first, the SIM card which is held by a SIM card holder communicates with a GSM modem through some digit command by receiving SMS from a cell phone or any other device. Next, it sends that data to the Microcontroller through serial communication. A microcontroller uses the standard AT&T protocol to communicate with GSM. Sending and receiving text messages are completed by sending the correct command AT&T sequence to the GSM module.
PCB Designing of GSM Module:
Now before designing the PCB for GSM antenna PCB you have to follow some rules and guidelines. You can go through a few tutorials available on the internet. Here we are going to discuss some important points which will help you with the design. First, draw the schematic as per circuit then check that whether it is matched with our circuit. Maintain a distance between all the traces, vias so that later when we are going to assemble all the necessary components it could be easy for us to place them properly without short circuit. EMI or electromagnetic interface is another factor that can cause instability for your embedded system. Generally, an antenna is connected with GSM to boost the radio wave signal so be careful about the EMI effect on the system, especially during transmission and reception. Always try to place the GSM antenna away from all the traces because. Don’t place it within in vias and traces. Make your design clean and minimize traces as much as possible. You have to ensure that voltage regulator that supplying power to the GSM module must able to handle sudden spike in current and It is better to have a thick and wide power supply copper connection so that it could be able to handle high current.
After completing the design we have to send it to a manufacturer so that they can manufacture it as per our design. Then we can assemble it so that it will be ready for use.
PCBMay could produce many kinds of Antenna PCBs for you,so we can understand that antenna PCB design is very important and its demand is increasing day by day. However, PCB designers need to be more aware and follow the guidelines for perfect antenna PCB designing. However, with the use of better quality software and artificial intelligence, antenna PCB design will become easier in the future.