What is it?
The RF performance of all Base Station, Mobile or Portable radios is quantified in a set of specifications given in deciBels (dB). One set of RF performance specifications describes the Transmitter performance, another describes the Receiver performance. For some RF performance specifications, a larger number is better; and for others, a smaller number is best. There are minimum acceptable RF performance specifications prescribed by regulatory authorities such as ETSI (Europe) and FCC (USA). Meeting these is mandatory.
Some RF performance specifications are more... Continue Reading
In the first part of this series, we explained the two main types of digital modulation, Phase Shift Keying (PSK) and Frequency Shift Keying (FSK) with an example of each – Linear Simulcast Modulation (LSM) – a type of PSK, and Continuous Four Frequency Modulation (C4FM) – a type of FSK. We also compared the spectral efficiencies of LSM and C4FM. In this part, we compare the costs and effect of delay spread of the types of digital modulation.
Effect of delay spread
Most digital radio modulation types are based on either Phase Shift Keying (PSK) or Frequency Shift Keying (FSK). Tait Principal Engineer Ian Graham is often asked about their relative advantages and disadvantages, so in this article he sets out to explore the subject.
To make it ‘real’, we will compare two actual modulation schemes: Linear Simulcast Modulation (LSM) – a type of PSK, and Continuous Four Frequency Modulation (C4FM) – a type of FSK. We will describe them, cover their relative advantages and disadvantages, then use an example simulcast system to show a practical comparison. Continue Reading
Tait Communications was recognized for its new high-tech campus at the prestigious EECA awards ceremony held at the Auckland Museum on Wednesday, 28 May.
Tait was named winner of the Christchurch Energy Champion award, in recognition of its leadership in energy efficiency and innovation during the Christchurch rebuild.
The $35 million Tait campus development is set on 11ha of land alongside Tait’s existing buildings and features the construction of an über energy efficient new headquarters for up to 350 of its Christchurch-based employees.
Principal Engineer Ian Graham explores a common question in radio system design: whether to deploy duplexers or to use separate transmit and receive antennas.
On the face of it, using a duplexer to reduce the number of antennas required by the system sounds like a great idea. But, as usual with RF, it is never quite that simple… Let’s examine the technicalities of both approaches. Continue Reading
Meet Rodney Mackrell. Rodney works as the Senior Design Engineer in Tait’s Usability Design team. We thought that maybe, like us, the rest of the world would like to get to know Rodney and the work he and his team do for Tait Communications, and see just how important Usability Design is to our clients and our company.
With Rodney we learnt about the process Tait takes to develop new client solutions, how ideas are formed and what working closely with clients looks like and what it can achieve. We looked around the workspace and discovered how this department works, how... Continue Reading
If you have never been involved in renovating your own house, you almost certainly know someone who has. It is a major logistical exercise in planning, perseverance, and above all, patience! Mostly, you will end up with what you want, but how often do you think “I wish I had shifted that wall/put in more storage/added another bathroom”?
There are so many things to decide, and only one chance to get it all right. And for most people, you will be carrying on your domestic “business as usual” amongst the chaos of upgrading your home.
Upgrading your radio system is a bit like that, but... Continue Reading
By Evan Forester, Marketing Campaigns Coordinator, Tait Communications.
Last week we introduced the new P25 Best Practice guides and website. Today we’ll dive a bit deeper to take a look at the first guide: First Steps to your P25 System.
I recently drove to a friend’s house and attempted a short cut. Unfortunately, I started by making the wrong turn. I ended up in a place I was unfamiliar with, but kept guessing the general direction of my destination. After a while, I literally found myself on the complete opposite side of town.
So much for finding a short cut.
If your first... Continue Reading
Click to visit the website and download the P25 guides
We are happy to announce the launch of our P25 Best Practice website complete with the first four P25 Best Practice guides:
- First steps to your P25 system
- Specifying your P25 system
- Procuring your P25 system
- Implementing your P25 system Continue Reading
P25 allows dispatch to have more control over defining talkgroups, prioritizing messages and integrating data.
P25 enjoys an almost unique capability in its ability to operate as a conventional, trunked, or simulcast system. As public safety agencies have already discovered, it is fairly straightforward from an engineering point of view to convert a P25 conventional network to trunking, while retaining the investment in the original network. Simulcast operation can be added to all or part of an existing trunked or conventional P25 system. Each mode of operation has its own strengths and tradeoffs which can be summarized as follows. Continue Reading